X is just as much of a cockup as it ever was; becoming more so from what I hear; You can have a million people come here, won't made a difference if there is no user retention.

I would agree, even from non-users, if someone sends me a link, I literally can't open it in most cases without creating a social credit score, I mean account... While it's not directly the same as a proof of concept, I would point you towards BitChat. It has continually gained more global adoption and in the places it's needed, user retention is high. The people that had it once for a protest are keeping it because you never know when you might need it again. In my opinion, Nostr is a lot like Bitcoin adoption. The places where it's needed it's adopted, which is proof of concept. And a lot of the places where convenience outweighs tyranny or the restrictions. but, especially with fourth-turning vibes around us, this could change quickly.

Bitchat sees a huge influx due to the French riots. Its lastability and user retention is yet to be tested, and tbh its UI / aesthetic is utter shite.

France is the most recent example. First it was Nepal, then India, and lots in Africa Look how many governments have banned it. Always a good sign it's being used...