Yeah, that's basically what I'm proposing. On protocol level it's possible to craft any type of note, but relays could check - if a note contains reference to npub that blocks mentions by you - they wouldn't accept or propagate your note. They also could stop returning your notes if the request is by certain npub.

Ah, I see. Thanks for the clarification. I'm not at all knowledgeable on how this protocol works in technical terms.