I think very few know about it yet. And it still suffers from small network effect. If regular social media keeps declining, and Nostr grows enough to have lots of different types of people, and be an at least semi-known name, people will probably come here.

Different kinds of people is probably more important than many think. Currently - probably due to those people being banned elsewhere and hence seeking it first - it seems like a very American, conservative, old Christian, anti-LGBTQI+ (particularly T), not believing mental illness is real (or that it's easily curable by eating steak, working out, etc.), look-at-me-I'm-a-REAL-man, etc. place. I.e. not a very welcoming place for anyone else.

Algorithms that the user can choose and tweak might also help with this.