I wouldn't dream of asking a non-techie to use nostr, even if they were into bitcoin. Most likely, a normie bitcoiner is afraid of hodling off-exchange. The keys thing is too much to ask of normies, they can't even remember the name of their cat for their password. Asking them to keep track of an unrecoverable key is like trying to make your dog wear shoes. A very predictable outcome. This isn't a problem that will be resolved anytime soon so far as I know. For a techie bitcoiner, on the other hand, it's a more reasonable ask to store a key. This might be the real reason nostr has a lot of bitcoiners; key-handling skill is a filter.