Threads has begun testing federation over ActivityPub. And they have blocked two important servers I administrate. The first server is the Mostr Bridge. The Mostr Bridge connects ActivityPub and Nostr together, so people can communicate across protocols. The second server is Spinster.xyz, which is arguably the largest independent feminist community online.
Tl;Dr: The most hateful and problematic instances that exist were wisely blocked by Meta, and the admins have found a workaround that lets them see Threads posts, but doesn’t let Threads users see their posts.