Why would you want that? I hate that "feature" on twitter.
Discussion
The main reason you're going to want it, is spam. If Nostr goes mainstream, spammers, fraudsters and advertisers will come and start assaulting us in our replies with ads. If and when that happens, we *are* going to need to have ways to detect and filter it, otherwise Nostr will become unusable for a lot of people.
"we cannot prevent people from seeing but we can certainly choose not to look"
mute or muffle is a fine feature to have but block is contrary to an open platform
You should be able to block whoever you want. It's your feed and your data. You're a sovereign individual, aren't you?
go for it. try and block someone from seeing your public data and see if it is effective
maybe you didn't see how this was discussed and how it would be implemented? if a client implements a blocking feature, it will be essentially a filter. for example. if i block you, i wouldn't see your comments on my notes while using the client that implemented the feature. they'll still exist, it's public data, and you can comment all you want, but as long as i continue to use that client, i'd never see them. to me, the user, it's a block. that's really the only type of blocking feature that can exist on an open network :)
No it isn’t
That’s on application level. Not protocol.