Perhaps someone starts a relay and then doesn't just accept anyone who pays, but vets the person before admitting them. Perhaps you check their profile, or they have to have a certain NIP-05 to show they are a "nosterpleb" or whatever, or they agree not to post porn or whatever to this relay and only post about certain topics, etc. Relay operators have that kind of control, right? And they could kick people out for violating the group's/relay's rules. Just thinking out loud, online...
Great interview on Nostrovia, btw!