Make NIP-13 the standard
Discussion
Spammers can do proof of work as well, usually with much better hardware than users
But while normal users post a few posts per day, the spammer does multiple per second? Isn't it different magnitude of required computational power, making spam way more expensive?
Sure, but ReplyGuy costs to spam are basically zero currently, and what income are these replies producing? At some level of difficulty, there is negative benefit to spamming this way. Relays can apply difficulty requirements for new npubs and existing, and keep raising the difficulty if needed
I like this idea. Huge PoW to register on a relay might make using disposable npubs useless (too expensive) for an adversary (spammer)