I’m on both. Threads is a bunch of anecdotes and isn’t very serious. Bluesky is popping and has reached critical mass. All of the serious news and sports journalists have been leaving X en masse and jumping to Bluesky. Facebook is full of people giving their (mostly new) Bluesky handle.
I finally nuked my X account which I had had since 2008 around a month ago. I hated to do it because I had the @ that was my just rare last name but I kept seeing some of the most horrible racist shit on there. There is no moderation at all.
I have been on bluesky since @echoreply kindly sent me an invitation in October 2023.
Edit: Original Dope thread: Has anyone gotten an invite to BlueSky? (Open to all now, invites no longer required)