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.)
Anything that lands on Meta’s servers is open for Meta’s use, however they see fit. Providing free training data for their algorithms just isn’t something everyone here is ok with.
Many of us are here consciously because we’re anti-corporate exploitation, not merely because our previous hangout spot fucked around, and Meta is king shit of corporate exploitation, and we want nothing to do with anything that’s helping them.
If by algorithms you mean things like GPT, all data on the fediverse is effectively public and arguably even easier to be collected than the likes of reddit, and is almost definitely going to be used to train models whenever or not the fediverse federates with threads.
There’s still significance in defederating though, specially when it comes to preventing “Embrace, extend, and extinguish”