I was a bit confused about this as well. Once Threads implements ActivityPub, what would federation with lemmy.world actually look like in practice? I understand how federation works between Lemmy instances, but how would a microblogging platform fit in? Would Threads users just be able to post to Lemmy, or would it somehow show up in a Lemmy community when a Threads user makes a post on Threads?
I’m not really understanding how two different services like Lemmy and Threads can be intercompatible.