Tbh I think the biggest problem to mass adoption of Nostr will continue to be the friction of onboarding new users. Literally just a few days ago a friend asked why there isn't an "oficial" Nostr app on both Android and iOS. I know, from an already existing user, seems like a non-issue. But for your average Joe, this defragmentation doesn't really cut it...

I think some things can still be done to improve this new awesome tech, in order to make it more user-friendly and marketable. Otherwise I don't see it reaching mass adoption easily.