I will leave it to Africa experts to tackle the Africa side of this equation. But I'll repost part of a related answer I've written.

The Marshall Plan, officially the European Reconstruction Program (ERP) was authorized by Congress in 1948, and administered by the Economic Cooperation Administration (ECA). The program ran from 1948 to 1952, and cost a total of $13 billion (or something over $65 billion in circa 2000 dollars). A significant condition for receiving funds was that the European recipient countries collaborate among themselves on economic integration, and so the 16 countries that signed up to the plan (which were, listed from greatest recipient to smallest: the UK, France, Italy, West Germany, Netherlands, Greece, Austria, Belgium and Luxembourg, Denmark, Norway, Turkey, Ireland, Sweden, Portugal and Iceland) formed a multilateral Organization for European Economic Cooperation (OEEC -West Germany joined in 1949).

The program worked as followed: the OEEC determined what each member country needed, based on national governmental requests). The ECA in turn transferred the requested goods, which were largely American-made products being exported. The American exporter was paid by the ECA with ERP funds, but the European recipient country did not receive the items as gifts, but as items to be repaid with loans. The payments for these loans were made in local currency and deposited in a counterpart fund which could be used by the national governments for other investment projects (it was generally understood that the money would not have to be returned to the US).

West Germany was in many ways a special case. Its Marshall Plan money was, as noted above, actually less than the money received by the UK, France and Italy, and was in fact not even the biggest source of aid it received in the postwar period - it received some $1.4 billion in ERP funds, but from the end of hostilities it had also received some $1.7 billion in the GARIOA program (Government and Relief in Occupied Areas), which was also US goods. This was also a loan, and so West Germany technically owed some $3.3 billion, and in 1953 reached an agreement where it would repay a third of this some (which was finally paid off in 1971). The remainder of the funds were in the country's ERP Special Fund, which actually continued to grow in size and make low-interest investments. Many of these loans were used for literal reconstruction in critical areas: transportation, export industries, housing and agriculture. The ERP funds later would be used in supporting international development, and ironically used by the German federal government to invest in small businesses in former East Germany after 1990.

So - the Marshall Fund actually has a few common myths associated with it: that it was meant to rebuild defeated Axis countries (especially Germany), that it was a gift, that it was a vast sum of money, and that it is singlehandedly responsible for rebuilding European economic prosperity as began to be experienced in the 1950s. While the plan played a role, it was as much psychological as economic.

That's some overview of the Marshall Plan. It wasn't a plan that "completely rebuilt Western Europe from the ruins" as much as it was a plan whereby the US government paid US producers to send requested exports to countries participating in the program (a number of which, such as Portugal and Turkey, had not even been combatants in the war at all, let alone suffered any damage) which was meant to foster greater European economic cooperation. Even here, the results were probably as much political and psychological as economic.

A final point I would like to note: comparing western Europe circa 1945 and Africa circa 1960 is already a very flawed proposition. Despite the massive human losses, infrastructure damage, and economic losses from the war, Western Europe was still one of the most advanced parts of the world in economic terms. Even in a country devastated like Germany, the human capital was still largely there - even if cities were in ruins with millions dead and displaced, the survivors were almost all literate and educated (many highly educated), with professional skillsets intact, and with personal years to decades of experience working in urbanm advanced industrial economies overseen by professional civil services. The UK, France, Netherlands, Belgium, Italy and Portugal also still maintained colonial empires.

In contrast, African colonies at independence were in a vastly different place. The population was overwhelmingly rural and agricultural, with very low literacy and education rates. Indeed, colonial administrations in Africa often prohibited certain levels of education or employment for Africans. Economic, social and political development in the former African colonies was therefore starting from a very different place than Western Europe after 1945, which was primarily rebuilding.

While this feels a little more r/theydidthemath, this does have a complicated false equivalence. And there are other factors that matter for the interpretation as well. But putting numbers in context is an important part of history.

So, let's just break down the "8 Marshall Plans" argument. The Marshall Plan was 4 years and sent 110 billion, which breaks down to 28.25 billion per year. Countries that received Marshall Plan Funding had about 292 million people, give or take, which adds up to 96.75 per person, per year of funding. Aid to Africa listed here from 1960 to 2020 consists of 60 years of aid. the population of Africa in 1961 was 290 million, in 2000, it was around 811 million, in 2020, around 1.3 billion. If we only account for 1961 population, then that aid works out to 51 per person, per year of funding. If we're counting the 2000 and 2020 populations, it falls to 18.5 and 11.5 dollars per person, per year of funding. This is at best half of a Marshall Plan for Africa.

Second, a big difference between the ongoing relationship between the US and Europe and the US and Africa is the existence of trade relationships. Part of what allowed European economies to grow in the second half of the 20th century post Marshall Plan was the existence of equal trade.

Let's take some economic powerhouses for comparison. In 2000, for Nigeria, the US' top import was Oil and Gas, Nigeria's top import was Fabricated metal products. In 2000, for Germany, the US' top import was Transportation Equipment, Germany's top import was Computers and Electronics. These are two very different economic relationships. Nigeria's is based on the extraction of natural resources, which employs very few people and does not involve the creation of general use infrastructure. Germany's is based on complex manufacturing, which employs many people and requires general use infrastructure.

To make this clear, to make cars, you need people to make all the parts that go into cars, which means that you need to make the infrastructure to support all those industries and then get those parts to the auto plant. If you look at the shores of Lake Erie in the US, every city developed with a specific part of car manufacturing in Detroit. Akron made tires, Toledo made windshields, Youngstown made steel. All of these required railroads and roads to move the products which could be used more generally to stimulate the economy.

Third, the non-math difference really does boil down to post-colonialism. 1960 is not a random year for Africa. Seventeen African Nations achieved independence that year; armed resistance to Apartheid began in South Africa. These changes saw a lot of new nations come into being. But post-colonial nations are starting from behind. They often have a significant lack of trained work force and limited economic infrastructure. Unlike Western Europe in the 1940's, they weren't picking up the pieces in a country that had been prosperous beforehand, they were starting from scratch.

While colonialism formally ended, international interference did not. Multiple Cold War conflicts occurred in Africa during the 20th century, undermining stability in the region. For instance, in 1975 the US sent 200 million in 2020 dollars to Angolan rebel groups in a conflict with Cuba and China(https://archive.org/details/forpresidentseye00andr). The post-colonial proxy wars made stability a hard to reach goal for much of Africa. And humanitarian aid balanced out by destabilizing investments doesn't actually help the country in question

Overall, this is a false equivalence. Numbers require context for interpretation and the long term effects of colonialism are still very present.

References:
European Population Numbers- https://photius.com/rankings/world2050_rank.html

African Population Numbers-https://blogs.worldbank.org/opendata/worlds-population-will-continue-grow-and-will-reach-nearly-10-billion-2050

Trade Numbers- https://www.census.gov/foreign-trade/balance/index.html

This is another one of those questions where the implicit thought that produced the question weighs the conversation down from the beginning. Either the point that the OP links to is being made to say, "What a waste that development aid has been" or "Africans screwed up where Europeans succeeded", both of which create a weight of presumption on any historical analysis.

There are obvious ways that the comparison breaks down. The Western European nations that were recipients of the European Recovery Program funds were considerably smaller in area and fewer in number than sub-Saharan Africa is in either pure size or in number of nations represented after 1970 or thereabouts. The rebuilding funded by the Marshall Plan took place in an era where there were relatively few constraints in terms of the scope of reconstruction and modernization efforts and where reconstruction was highly concentrated but they also targeted countries that were structurally at the center of the global economy that had developed since the mid-19th Century. Development aid since 1960 in sub-Saharan Africa was diffuse both in what it was allowed to address and in the constraints associated with its distribution (constraints set both by donors and recipients). Those constraints were also highly variable over time: development aid has moved its goalposts and formalisms regularly. Development aid was not targeting countries that were at the center of global economic structures but instead new countries that had been under exploitative colonial rule for anywhere from two centuries to a half-century. The Marshall Plan took place during a postwar global economic boom (which it may have played a role in facilitating, though this is still very much contested by historians) whereas postcolonial development aid in Africa began to be offered as the postwar boom cooled and then during the traumatic oil price shock and global economic disruptions of the 1970s. To some extent, the Marshall Plan was spared debates about what exactly it was trying to remedy: the devastated industrial and material landscape of much of Europe provided a clear answer and a clear target. Development aid in postcolonial Africa was subject to intensely contrasting forms of orthodoxies about what exactly it was meant to be doing and why. The Marshall Plan's designers were either intensely solicitous of and consultative with government leaders in the states of the US's WWII allies or they were able to act directly in the case of the former Axis powers under occupation. Development aid to sub-Saharan recipient nations was mostly designed, debated and implemented by donor nations and international institutions, often with little consultation but also with little direct control over implementation of aid plans on the ground.

There are also some fascinating things to consider about what the comparison might reveal. Arguably the major motivation for both forms of aid was to retain the loyalty of recipient states and their leaders during the Cold War, and to block the influence of Communist parties and advocates. Economic historians and economists who credit the Marshall Plan have often described as a successful example of development aid that had many of the same premises as aid to African nations under the so-called "Washington Consensus", suggesting that there is at least some valid basis for asking why one succeeded and the other failed. You could look at a few specific cases of development aid in sub-Saharan Africa to reinforce the validity of that question where the aid in question resembled the structures used in the Marshall Plan to a greater extent--I think most notably Ghana in the 1980s and 1990s, where the government permitted extensive managerial interventions by the IMF and the World Bank, with arguably good outcomes.

I think on the whole the differences vastly outweigh the similarities. A good example might be Congo (Zaire), where development aid was not really provided in any form in the first decade or so of independence, but where the military and diplomatic interventions of Cold War powers and the former colonial power of Belgium largely ensured that the new government was enmeshed in civil war and insecurity and had no hope of achieving any kind of meaningful development plan. By the time the United States was providing aid ostensibly intended to help encourage economic development in Congo in the 1970s, it either went into the personal wealth of Mobutu Sese Seko and his supporters as a way of buying their loyalty as American allies or to a handful of boutique projects that had little underlying rationale. The only thing that makes that similar to the Marshall Plan is that both were intended to block the influence of Communism, which they succeeded in doing. After Mobutu fled power, successive Congolese governments have lacked real on-the-ground power in much of their territory and no international agency has been able to substitute for that kind of sovereign authority. Moreover, Congo's structural role as a supplier of raw materials for overseas production, often at the barrel of a gun held either by local military forces or outside plunderers, has been largely continuous from Leopold II's rapacious stripping of rubber through genocidal violence up to current extractions of diamonds, industrial minerals, and rare earths.

To develop Congo's economy as a fully rounded, diversified economy which returns value to its own citizens and supports public institutions was always a very different kind of proposition than rebuilding France or Germany's existing industrial and commercial base back to their pre-eminent prewar status: as a territory with modern boundaries and governmental institutions, Congo has never had an economy that even remotely serves the needs of its own people. Development aid, if it was serious about that goal (and it never was), would have had to build economic institutions that were completely at odds with Congo's existing experience and structural place in the pre-1960 economy, with all the social institutions required alongside that. (Right up to 1960, none of the existing factories or firms in Congo employed Africans in any but a lower-level managerial role, and the Belgians had largely blocked any Africans from receiving advanced education until a year or two before independence.) Imagine if the Marshall Plan had needed to provide support for the creation of an advanced industrial, manufacturing and service economy from scratch in 1947 in a European state and you might sense just how different the prospects have been. Development aid in postcolonial Africa careened between different orthodoxies because on some level the fundamental challenge of completely undoing colonial economic and social institutions and building something new was neither fully admitted by outside institutions who had a vested interest in downplaying the structural impact of colonialism nor was seen as fully practical in terms of the expense and effort that would be required.

And yet development aid went on--again, perhaps simply because it was a way of buying influence and affinity from postcolonial leaders. But also I think you could credit some good intentions here and there despite a parade of serious errors and failures, a real intent to try and help put postcolonial African states into a different track. The scope and scale of what development might be trying to accomplish if one takes it as seriously intending to live up to its stated goals are simply so big and so challenged that those accomplishments have mostly been elusive at best.

This question encompasses an enormous amount of content. I will first point your attention to some aspects on why the Marshall Plan seems to have been effective in promoting Western Europe's post WOII economic boom, the conclusion to which I will link with the some perspectives on the general effectiveness of foreign aid.

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The academic consensus on the effectiveness of the Marshall plan is that it was small relative to the size of European Economies, and that the popular image of it 'rebuilding Western Europe' is inaccurate. Eichengreen & Uzan (1992) suggest that it increased Western European's national income by 1951 by about 2%. However, it did set Western Europe on a path that would enable a very strong growth trajectory from 1951 to about 1972.

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After WOII, European Economies were in crisis. Damage to infrastructure caused by WO II drastically decreased the productivity of countries. This would require a well thought out long term investment strategy to regain productivity levels of the pre-war period. At the same time, the pressure on governments to increase standards of living in the short term was large, after years of suffering. The Marshall Plan, though small in size, both supported governments in this trade-off, by making available some funds to go to (American bought) basic necessities such as food.

In exchange for this financial aid and thus relieving some of the short term pressure on governments to satisfy the immediate needs of its citizens however, the Plan came with two main types of conditions goverments had to meet. First of all, governments had to get approval for how they invested their money. In this way, the US pushed Western European economies towards long-term structural investments. Without the aid and subsequent conditions, those would have been politically unfeasible. Second of all, it came with the condition that Western European economies align with the free market principles governing the US economies. This was not as obvious as might seem at this time. The Great Depression and the self-proclaimed economic succes of the USSR had decreased faith in the free market relative to centralized planning economies in parts of Western Europe. However, as it turned out, many of these free market principles that the Marshall Plan incentivized (I am purposefully remaining vague because this is an entire essay in and of itself, but think of free price setting, limited labour market restrictions, incentivizing private investment, ...) turned out to be much more effective in increasing long term growth in Western Europe than the USSR's policies in Eastern Europe. Part of this growth difference can thus be attributed to the conditions of the Marshall plan.

In short, the Marshall plan was not effective because a large amount of money was made available, but because it came at a time that it helped stabilize Western European economies, and came with requiremants that created some of the conditions that helped Western European economies with their immense growth from 1947 to 1972 (though there are many other reasons for this growth, such as a positive labour market dynamic because of population growth, a stable global financial system, technological advancements, ...).

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The historical lessons from the Marshall plan thus indicates that it is not necessarily foreign aid, but financial stability and good institutional reforms that enable market forces to do their work and induce growth. The strength of the Marhall plan was that its conditions strengthened Western-European financial & political stability through debt relief and immediate aid, while pushing governments towards productive investment and pro-market institutional reform.

Similarly, empirical studies on the effectiveness of foreign aid in increasing economic growth in developing countries emphasize similar aspects. The quality of political governance is seen as one of the most crucial moderators of the effectiveness of foreign aid in inducing growth in developping countries. But even then, foreign aid in the 1980's did make a shift towards demanding liberal market reforms with only mixed success.

There's really no easy answer here: the academic community of development economics doesn't have any definitive accepted consensus on the effectiveness of foreign aid. It is too context dependent. The Marshall Plan seems to have been conducted under some ideal circumstances for foreign aid, and did demand useful political and economic reform. At the same time its effectiveness need not be overstated, and foreign aid has been effective in some cases in Africa as well (see Tanzania, Botswana). The current trajectory of academic development economics is, as exemplified by authors such as Nobel Prize winners Duflo and Banerjee, focusing on what conditions are necessary for effective foreign aid interventions. If you are really interested in this topic, Poor Economics by those two authors might satisfy your curiosity.

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How effective was the Marshall Plan --> Eichengreen B., & Uzan, M. (1992). The Marshall Plan: Economic effects and implications for Eastern Europe and the former USSR. Economic Policy, 14, 13.

Why was the Marshall Plan effective --> Long, J., & Eichengreen, B. (1992). The Marshall Plan: History's Most Successful Structural Adjustment Program. Discussion Paper Series - Centre for Economic Policy Research, (643), Discussion paper series - Centre for Economic Policy Research, 1992-03-01 (643).

Foreign aid effectiveness and political governance --> Ekanayake, E. M., & Chatrna, D. (2010). The effect of foreign aid on economic growth in developing countries. Journal of International Business and cultural studies, 3, 1

General paper on examples of effectiveness of foreign aid in Africa --> Edwards, S. (2015). Economic Development and the effectiveness of foreign aid: A historical perspective. Kyklos, 68(3), 277-316.