Enshittification isn’t always driven by a conscious person or organization with an agenda, much less one with an agenda of short term financial gain. Sometimes the aggregation of a bunch of individual decisions causes something to get shittier. Or better. Or just different. 4chan is not at all like it was 20 years ago, but it wasn’t because of corporate influence. The culture just changes.
So if the question is whether the fediverse might someday suck, I think the answer is probably yes. It remains to be seen how it will suck, who will have caused it to be that way, and whether there will be other nice things about it.
20 years ago it was the people who worshipped Jack Welch, not realizing (or not caring) that he was running GE into the ground.