>I also suspect most people aren't nostr-only ...
I think there are more reasons. Because nostr doesn't give them enough stimulation high they need from other algo platforms that can be more predictable. 

Proud to say I've never used twatter but I can imagine the desire, that and most other big-tech platforms. They leave because the overlords do something they don't like but quickly forget when things over here don't stimulate their addiction enough. That and the whole what are the odds it'll be me that gets banned or whatever risk vs. reward cycle.

I'm also a very light social user, maybe like 30 mins/day besides chatting with our team.