The fact that only 0.1-1 % of humans are intetested in censorship-resistance and privacy at all is one reason. The other is: the mainstream is fucking afraid of using 'keys'. They are not able to grasp that concept. They can't handle self-hosted things and they don't want to. They lose their fucking passwords and need someone to recover passwords for them when they are lost. BTW: The UX is ten times worse for normies. Try explaining to normie-internet-users that their data/posts are gone now cause a relay is offline and they should have run their own relays. Or that they can't use image-uploads cause someone needs to pay for the hosting. Or that half of the apps don't work very well and are only vibe-coded over one weekend and then abbandoned. I spent a lot of time showing the Nostr protocoll and different nostr apps to people. They mostly don't like it. Bad UX. Imo: Nostr is niche. And will always stay niche.