Are people actually worried they would would see straight up ads coming into their mastodon feeds if their server federates with Threads? That’s a pretty wild assumption to make.

Not only are they worried, they think that this is a foregone conclusion. They think it's more important to block Threads preemptively than to actually make an informed decision ... looking if Meta would actually somehow misuse federation and then block them, should that happen. I've seen Lemmy instances block Threads before they block any neo-nazi and pedo instances. Seriously, WTF. The hysteria is insane. Threads content can't currently even show up on Lemmy.