If this is the case, I urge EVERY instance admin across all currently federated apps to blacklist threads.
If threads is allowed to federate with these apps, it will outweigh all contributions to these apps, and when Meta eventually defederates (which they will), the vast majority of the community will be lost.
PLEASE HEED THIS WARNING!
Will Meta try to fuck over Fediverse? Very likely.
Is it mutually beneficial to be federated? Yes.
Mastodon will never be the biggest player around for microblogging because too many people nope out when presented with server selection, even with defaults.
Take whatever users you can now. Threads app has no “following” chronological timeline, probably never will. Show people you can do that from Mastodon and it’s clients.
It’s likely that one of the reasons Meta is using Activity Pub is upcoming EU regulations on electronic platform gatekeepers. They will have to open them in some way anyway. It’s likely regulators will be checking if Meta is playing nice with Threads.
Threads can try to EEE Mastodon but so can Mastodon. Mastodon can fuck over Threads in many ways too, mostly by providing better experience and it’s better than isolating.