Afaik, whenever an Activitypub instance has defederated from another it has always had to do with some combination of bad user behavior, poor moderation, and/or spam. Are the various instance admins who have decided to preemptively block threads.net simply convinced that these traits will be inevitable with it? Is it more of a symbolic move, because we all hate Meta? Or is the idea to just maintain a barrier (albeit a porous one) between us and the part of the Internet inhabited by our chuddy relatives?
(For my part, I’m working on setting up my own Lemmy and/or Pixelfed instance(s) and I do not currently intend to defederate.)
I started a community to track the H5N1 global outbreak but I do NOT want to moderate it long term; if it picks up, the anti-vax/Plandemic people are going to start showing up (they already do sometimes in the subreddit for it). I feel like opening the doors to Threads is going to hasten that.