There are some builders of AI on BlueSky but far fewer. It's mostly the other sciences that have migrated, because X actively suppressed that type of content on X. Its not uncommon for a Bluesky scientist to have 10x the engagement on Bluesky with a tiny fraction of the followers.

I’ve seen similar patterns with some technical subcommunities on Mastodon. Low follower numbers but vastly higher engagement and overall better signal to noise ratio in the replies.

Maybe instead of there being one big platform, communities will settle into different ones.