i ONLY want to conter your argument with email and activityhub: on email people choose to send stuff to a very limited amount of people except maybe newsletter and scammers. with threads, which should have already multiple times of osers compared to the fediverse, will flood the content to /all. Of course there are cool people but i think the entire fediverse culture will be blown away by threads in an instand. And with their weird moderation (especcially small) servers here will have large problems trying to moderate it
but by email there is no mass broadcasting to the public so it does not need to be moderated