what do we do against this?
Once again: I want to be able to turn off people's ability to PM me. Checks for "accepting PMs" doesn't even have to be in the codebase for every type of fediverse server code; but each instance that decided against PMs, they could check incoming messages vs the recipient and, if rejected, simply send back a message saying "This user is not accepting PMs."
Ah, that old GOP favorite, the "Schrodinger's Joke" defense against encouraging stochastic terrorism ....