Ultimately the fediverse is still an experiment. It clearly works, and in isolation many of the services (Lemmy, Matrix, etc.) work well enough on their own.

I'm not optimistic about anything at this point. The fediverse might die; it might not.

There could be huge incentives for them to convert Mastodon users over to Threads, based on their internal analytics, in which case the headache would be worth it.

Meta won't be dead anytime soon, but it's clear that they've made some risky plays, which means their decisions are going to continuously be less risky.