>As for spammers, that's inevitable. What matters is how you rate-
limit the number of events they send.
Yes but no. Every alternative to Nostr gives users Administrative controls. Nostr relays are basically a public notepad file that any person can write to as much as they want.
> And it would also mean paid relays being a more attractive solution
Paid relays are not a solution at all. Basically, Nostr will be so terrible that people will need to pay to have a good experience? That will hurt adoption.
If most free relays won't be sustainable, why would anyone choose Nostr over anything else? The Fediverse is thriving and growing and interacting across thousands of servers each day. Less Nostr relays = more centralization.
I didn't even get into the centralization of media uploads on Nostr yet and how the costs will sky rocket. That's another discussion.....kinda