That only works if the users who would be recieving your posts know to use your new relay. Tell me, how would they do that? I've seen people replying to posts that I can't see. What do I do about that? How do I find out what obscure relay I need to add to see that post? How do I know what a relay is blocking if they don't want to say?

In theory I can choose my content, but in practice it's impossible to tell which relay options will have the effects I want.