Any relay on the internet is not private. I access mine over wireguard. But once we have encrypted notes you can do interesting things like private relay backups, private contact lists, private block lists, etc.
Discussion
but we do have encrypted notes don't we? Nip04
Those aren’t encrypted notes, those are encrypted text DMs
I'm a bit confused about the difference. Does it have to do the fact that nip04 notes use asymmetric encryption? Would encrypted notes use symmetric encryption instead?
nip04 is meant for encrypted text content (DMs), not arbitrary notes. The encryption doesn't cover tags or kinds. With encrypted notes you could send private likes, retweets, posts, etc.