Maybe I'm foolishly optimistic, but it seems like people want a platform with less unfettered bigotry and tools for mass blocking.
I don't have an account on either site so I'm only really seeing bits and pieces here and there but what I have seen is a fair bit of "wow it's so much nicer here! it reminds me of twitter back when it was full of normal people!" type posting.
edit: also lots of wailing from hatemongers who feel deplatformed because nobody is being strapped into a chair clockwork orange style to read their unhinged rants.
Post-election - Bluesky has become a lot less fun for me. The quality of posts and threads has gone downhill. A huge number of shitlibs, turbolibs, grifter libs, resistance libs, the most tedious rockstar libs, etc have come over from Twitter so it's like lib Twitter but far worse. It's a lib echo chamber due to Bluesky's nuclear block and the libs block super-fetish. Also there are LISTS of people they block which are shared. Libs are blocking leftists they never spoke to or even saw the display name of.