The hurdle to that is much greater here since there’s a common protocol adopted by multiple open source projects (of which Lemmy) which allows interoperability. If a profit-driven group would try to capture it, people could move instances/use a fork/use a different but similar activitypub project like kbin, etc.

At least I think that’s correct? It seems to me there are multiple lines of defense which each have a good amount of redundancy.