Nostr really could use a robust npub rating system. i.e. what would be cool is if you could just give this npub a 0 rating (perhaps even add a comment)... then, when I receive an unsolicited DM from this same npub, I would quickly notice that it comes with a low rating among all my follows; and that nostr:npub1aqakd28d95muqlg6h6nwrvqq5925n354prayckr424k49vzjds4s0c237n has even provided a detailed explanation to accompany the low rating he gave.

(*I have heard of work being done in this direction; but I haven't taken the time to keep informed on progress).