Why was the Cold War framed as "Capitalism vs. Communism" as opposed to "Democracy vs. Totalitarianism" ?

Couldn't the U.S. have framed the Cold War as a conflict of "Democracy vs. Totalitarianism" as opposed to "Capitalism vs. Communism" and become allies with these governments?

First of all, lets understand in a short intro on how communism as a ideology became more and more widely known and accepted as the world neared the end of the Second World War.

In terms of ideology, the outcome of the Second World War seemed to favor the left and the Soviet Union, at least in the short run. Almost everywhere people yearned for signifi-cant socio-economic reforms, for structural changes in their economies andpolitical institutions, and for improvements in their living conditions. In most countries, right-wing groups were discredited because of their association with the defeated Axis powers. After fifteen years of depression, war, and genocide, many of the bourgeois middle-of-the-road parties of inter-warEurope also were weakened. In contrast, Communist Party membership soared because of the major role Communists played in anti-fascist resistancemovements. In many countries the Communists and their allies appeared ready to take power either peacefully or forcefully. US policy makers worriedthat wherever and however Communist groups attained power they wouldpursue policies that served the interests of the Soviet Union.

-Origins of the cold war: An international history

As you see, The end of world war 2 was extremely devasting to european government .The government elites and the rich while affected were still better off then the commen people.

Rationing of food, Fear for their loved ones, anger towards a government for entering a war which they did not see as worthwhile (Note: The public mood did change a little as the end of war neared due to a variety of reasons.). The government and the ruling powers promised the people sweeping changes and reforms and permanent changes in social hierarchy after the war.Old institutions were promised to be turn down in favour of new which did not discriminate against people on the basis of class,religion,sex or creed.

While not directly an increase in communism,the end of the war was marked by an increase in the support for left wing parties, which included the communist parties.

The Americans however were concerned with this.American foreign policy thinkers were of opinion that the communists played fair only until they came in power. American policy thinkers were of opinion that the communists(no matter which country they came into power in) will always follow the order of soviet union and together work towards their so called plan of "world communism".(Which btw was complete tosh because the Soviet Union under Stalin had long ago abandoned the idea of world communism. In fact, the differing politcal opinion difference was one of the main point of contention between Stalinista and Trotskiests)

So, framing the struggle as a "Democracy vs totalitarianism" would be harmful to American agenda as in such a sytem, America would be open to the most obvious attack that it was quite morally and ethnically hypocritical of Americans to support "Democracy" and yet stop communists from being taking part in such a set up (if they banned communists from contesting elections)

Some example of what I mean about obstruction of communists in taking part in free and fair elections:

Although not crude, heavy-handed, and brutal as was Soviet intervention in Eastern Europe, US and British intervention in Western Europe was extensive and effective. As they liberated and occupied Italy, the Americans and British moved quickly to exclude the Italian Communist Party (PCI) and other leftist groups from power. Rather than resisting, the PCI sought to work with the Italian government headed by Marshal Pietro Badoglio. Silvio Pons, using newly available Soviet records and PCI materials, examines the constraints placed on Italian Communists by Stalin’s reluctance to jeopardize relations with his coalition partners. Pons suggests that Stalin did not plan to spread Communism to Western Europe. Rather, Stalin sought to prevent Communist parties in Western Europe from taking actions that could precipitate the formation of an anti-Soviet Western bloc.

Economic reasons why the ideology was made a "Capitalism vs Communism"

Although economic conditions improved in most of Western Europe in 1946, recovery faltered in 1947 as a result of an unusually harsh winter and a fuel crisis producing social unrest, political instability, and declining foreign exchange reserves. US officials feared that economic distress would translate into support for Communist parties, especially in France and Italy, or expanded controls on trade and investment. To solve these problems, the United States provided sixteen Western European nations with billions of dollars of economic assistance that enabled them to devote massive resources to reconstruction and to expand their exports without resorting to socially and politically divisive austerity programs.

The introduction of Marshall plan was done for several reasons but one of the main reasons was to immediately curb the growing support for communists in the european countries faced with economic hardships.

With a massive investment in infrastructure, reconstruction and stabilisation of economies in 16 different nations, The United States hoped to showcase that even without communism, large social upheavals and changes in class can be done. The only thing required, they said, was a small push.

This can be clearly seen in future years, when The Western block continuously showcased West Germany as the poster boy of capitalist success and achievement while the East germany fell between West germany more and more every year. Using hard tangiable statistics and data, it was more easy to showcase victory in a "Capitalism vs communism" model while the same could not have been done in "Democracy vs Totalitarianism" model

And finally my favourite form of argument Whataboutism?

America overthrew democratically elected government in multiple nations to replace with dictatorship to "check the spread of communism".
Inside america, Various obstacles were placed to curb the voting rights of black and other non -white minorities via a incestous interplay between the federal and state governments of south
America prohibiting or obstructing communists and similar parties from contesting elections in a free and fair manner.

How could the USA explain away such away hypocrisies in a "Democracy vs totalitarianism" narrative.

#TLDR:

1)At the end of world war 2, Popularity of communists was more than ever.People were not ready to go back to old pre-war society after 15+ years of hardships. America on other hands did not want Communists even in 10 mile radius of any government power.So they ensured maximum obstruction to communists in all newly freed nations of europe post war. It would have been difficult to do so in a "Democracy vs Communism" narrative as the americans would have to allow the people to elect the communists in a free manner if they wanted.

Capitalism was by then clearly shown a superior model of development to communism after almost 25 years of rule in Soviet Union. Also using Hard statistics, economic prosperity and economic upliftment of people- the americans could easily prove capitalism as a superior model more easily, thus they prefered the "Capitalism vs Communism narrative".
It would have been hard to explain american hypocrisies in a "Democracy vs totalitarianism" narrative

(Note: if you have any doubts about the TLDR, read the complete answer before asking any question.Dont be a lazy fellow)

#Sources:

Origins of cold war: An international history
Global cold war: Third world interventions and making of our times