@grrrr_shark I've seen people point to https://fediblock.neocities.org/. I don't know whether it has anything to do with anything that was named "fediblock" in the past.

FWIW I am on an instance that blocks ~no other instance (and haven't created any blocks myself) and saw something in these directions (TERFy, humanity-denying, ...), IIRC, twice in the last 2yrs+. If my experience is reasonably typical, then "block on first offence" might be reasonable?

BTW. Note that you can both block instances (no communication possible whatsoever), silence them (something akin to unless you follow a user from there, you won't see their posts in timelines; i don't remember about replies). There was one other level of blocking that I can't find now, which was morally equivalent to blocking, except for remote users who are followed by a local user.