Someone posted a link to a Mastodon post (edit: found the post) from the admins at lemmy.world which basically stated that they would take a “wait and see” approach. I can’t find the post right this moment but I’ll keep looking. In any case, it seems lemmy.world will not be defederating, at least until Meta does something bad enough, whatever that may be.

I also saw a post from vlemmy.net about having to defederate from another instance, and the whole post was extremely transparent and well put together. I suspect they will not be defederating from Meta, as it seems that they don’t want to defederate from anyone, barring laws being broken. With that said, they seem to be based in Ireland and I’m not sure whether they’ll have to defederate from Threads for legal reasons or not.

There was a comment somewhere that had a list of servers that had already taken the stance of federating when possible, had not taken a stance at all, and had preemptively defederated. I’ll see if I can find that one for you, as well. I misremembered, it was a list of Mastodon servers, not Lemmy.

I’m not sure if this is helpful, but I hope it at least points you in the right general direction! I’m in kind of the opposite boat from you - I am disappointed that lemmy.world will be federation with Threads, so now I’m poking around to find someplace that suits me better. It can be challenging figuring out where instances stand!

I couldn’t upvote or comment until I added a lemmy.world account. Now it seems like I can upvote and comment from my Beehaw account? Definitely strange, but the app is clearly in development, so hopefully that’s an issue that gets ironed out quickly.