one of the things I have noticed is that the general users in Nostr are quite short attention span, e.g. long-form content probably don't work there, and ppl have less willingness to rely on something thoughtful too; I guess it could be due to the habit in social media, ppl prefer to read something fast and easy.

As for your Q why, maybe Bitcoiners know that their time is limited, might as well read a book or learn some skills...I don't spend much time in Nostr too.

how about SN 👀