@Gargron - is any of this related to Meta's Threads?
That company's lax attitude towards moderation could become a beacon for spammers to set up accounts there and then propagate their spam to the rest of the fediverse.
I am not an admin, so I don't know what goes on with the server side of things, and I am probably over-simplifying.
@galacticstone No, not at all related.