It's a hard call, for sure. We don't want to make onboarding new legitimate users any more difficult than it already is, but we also need to have ways to mitigate spam like this.

We can do some of it via web of trust, but that will heavily impact new users if we make it automatically filter out anyone who doesn't yet have any followers from within our web of trust. 

Someone else had an idea about being able to flag your post as requiring a small payment in order to reply. I think this would be interesting. Anyone could try and reply, but you just wouldn't see it if they hadn't paid.

This also needs to be fought primarily at the relay level, since this spam is going to be taking up space on the relays, even if clients give users tools for not seeing it.

Requiring a small payment to post any note to a relay is something entirely possible with Lightning and eCash + Nostr Wallet Connect, and it would help make relays more sustainable, too. The downside, of course, is it may cause legitimate users to post and reply less often, since there is a cost, however small.

@Mike Dilger seems to have been able to keep the spam off of his relay, but I think the way he did so would probably have an impact on new users being able to post to his relay, so it would not be a solution we would want all relays to implement.

nostr:nevent1qqsw788j7fe664hq4geqlner4zgnm3zsffyxyfe8tlu4s8w67htjvwcpp4mhxue69uhkummn9ekx7mqprpmhxue69uhhyetvv9ujumn0wdmksetjv5hxxmmdqyf8wumn8ghj7mmxve3ksctfdch8qatzqy28wumn8ghj7un9d3shjtnyv9kh2uewd9hsyg8wzxjalaqvrxj4taqlus453uqwvxxfzgjky2hr0dkzhdnmwmzwfyc54a2r

So, it seems to me that the "postage required" method is likely going to be the most effective with the least impact on new users, even though it WILL require them to have some sats ready to go before they start posting.