The reason Nostr growth is stagnant is mostly cultural, not technical, IMO.

Sure there is still some deep weirdness with the UX compared to the centralized services (like being unable to delete or undo posts/likes/reposts, or that the phone clients still have weird little bugs and are still under featured in some basic ways).

Remember, there was a LOT of excitement here not long ago, and many people left after joining despite the fact that it kept getting better. Which should tell us something, no?Why was this? My guess is because there's only like three topics of discussion here:

1. Bitcoiners talking about how great Bitcoin is

2. Bitcoiners talking about how great Nostr is

3. Bitcoiners talking about politics

There's outliers who break the mold for sure (and we need more of them), but even Bitcoiners are interested in other things and going where people outside of Bitcoin are, and so even most Bitcoiners left.

In many ways Nostr is more fully featured compared to Twitter/X, and in other ways it's even less buggy, but despite the bugs people still use it because that's where so many interesting people are and talking about all sorts of things. Most people are fine dealing with the bots and whatnot and for very few is censorship a real selling point (for now).