/u/amphicoelias

Good questions, however I think you are mistaken on several counts.

As far as I understand, these mostly stem from immigration during the 50's and 60's to fill labor shortages.

Yes and no, you have to first define who are "British Indian" and "British Pakistani". Some come not directly from south Asia but rather from the Caribbean. This chart tells you why this can be important. The UK used to have fairly open immigration policy from some parts of the Commonwealth, and for specific groups. But this was changed through successive Immigration acts in the 60s-70s. The sharp rise and decrease in immigration from the Caribbean is due to the 1962 Act. However, immigration from south Asia continued at a fairly high level, increasing even further into the 90s.

The Indonesian community in the Netherlands consists mainly of people expelled from Indonesia, like the Indos, Belanda Hitam, and Moluccans (article in Dutch).

On to the former Nederlands Oost Indie, there were big waves of immigration in 1945-6, 1949, and again in 1957-9, and the early 60s. The first few waves had to do with repatriation following WW2 and the full independence of Indonesia. The 1957-9 period saw nationalization of Dutch companies and assets, the suppression of Dutch-supported RMS, and the early 60s saw economic calamity. Since that point, immigration from Indonesia had largely dropped down to small numbers.

Most of the waves of immigration from the former Dutch East Indies I mentioned are by those with strong attachments to the Netherlands.

The Netherlands had similar labor shortages during that time, but it filled it with Turkish and Moroccan guest workers.

Indonesia didn't remain in any sort of Commonwealth with the Netherlands except for the very brief Republic of the United states of Indonesia period. So there were simply no avenues for immigration, and the Indonesians who did immigrate to the Netherlands were more connected with the Netherlands than to the rest of Indonesia. This is why when the Netherlands faced labor shortages, it did not settle on a guest worker program with Indonesia, rather it made agreements with Turkey and Morocco.

Among these immigrant communities, the reality is quite different. Indos and Chindons who moved to the Netherlands are considered to have acculturated very well and have good economic opportunities. Descendants of the Maluku RMS sympathizers were under-served by the Dutch government who maintained the illusion of "we'll get you your independence soon -- just hang around this refugee camp in the meantime!" Hence they face significant challenges today.

The total number of Moroccan immigrants were not large. But they tended to have very high reproduction rates. This is why they are a very large community today. The Dutch government is considered to have done a poor job in helping them integrate, and held the view of "no need to learn our language and culture as you won't be here longer than we need you as workers!"

Check out this very nice paper with nice charts from the Tinbergen Institute.