Swahili and Indonesian are primarily second languages, used as lingua francas amongst large and diverse populations, so linguistic changes are mainly driven by non-native speakers, as opposed to the languages you listed
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This is a great observation.
A clarification comment here to help explain what is going on here- re: the 'non-native' part of the comment above.
Swahili specifically is a second language to a population speaking a very very diverse set of first / primary languages.
Swahili is spoken in East Africa - Burundi, Congo, Kenya, Uganda, Somalia ( southern tip) Rwanda, Tanzania.
Kenya and Tanzania have the largest part of speakers and in Tanzania, there are over 20 'first' languages and in Kenya , there are at least 20 'first' languages as well.
Also important to note that Swahili is formally taught in primary / grade school, alongside either English or sometimes French, to a population that already speaks a different first language used by a much smaller population.
The point here is that there are many many first languages that are sources for "borrowing" into Swahili but that borrowing has to be adopted across all Swahili users who will not share that first language.
This means that only the 'easiest' / 'lowest friction changes' make it through over time into Swahili as all words also have to be accepted by speakers having other "first' aside from the ones that each word or language component was 'borrowed' from.
Swahili and Indonesian were primarily second languages, in the 20th century. But now they are very much first languages as people are learning them from childhood simultaneously with their ethnic language.
perhaps we should qualify the claim by pointing out that 20th-century swahili and indonesian are simpler than creoles, but have now been replaced by more complex creoles