This is incorrect.

If you want to have pocket networks of limited size, then maybe you can keep using nostr for hobbyists and outcasts.

But Kanye is never gonna host his own server, and millions of people self-hosting following Kanye will never be performant without massive indexing.

You're just re-injecting nostr into the design for no benefit. (But nothing stopping people from using Pubky that way if they must...)

It is too inefficient to have everyone syncing everything locally, hence why Bitcoin doesn't scale well.