Bluesky is currently an excellent platform for the scientific/academic communities—but it is horrible for most other uses. I recall seeing several influential voices help drive the migration to Bluesky when MElon began altering X’s recommendation algorithm, effectively shadowbanning many science-related accounts (those with large followings whose posts were suddenly hidden from their followers).
Interestingly, Bluesky offers no formal guarantees that similar practices won’t happen there. However, its social and political environment is perceived as more tolerant—or at least less self-destructive—than Xitter, making it feel like a relatively safe space.
Nostr missed the boat. It’s now unlikely to attract academic/scientific voices unless something dramatic happens. That’s a missed opportunity, as this is one of the most valuable communities a social platform can have.
I also suspect that they would not move to Nostr.