Granted that visibility should not be a claimed right, the basic difference is that Nostr offers a basic feed (the fake “Global”) that is so chaotic that it is used by few to discover new content. I think the solution is to create one's own circle and with that go and merge with other micro groups, thereby growing the social graph. And at the same time enhance the discoverability of content through search and thematic structures. Shadowbanning does not seem to me at all the correct term for the current situation.