Funnily enough the best market fit for nostr IMO is primary schools. As a sort of roblox for social networking, bundled with other chromebook edu-stuff. Kids can learn to hack together things for their class, bump up against hard logic problems, lose keys no issue. And keep it all to safe relays, each classroom or school isolated, sometimes cross-class or cross-school connections for fun. The tough thing is that nostr has this reputation that will put all parents and primary schools right off. One google search and over. So you'd have to hide every trace of nostr, even the npub/nsec encoding, a complete and total rebrand. But that's actually where the fit is. Nostr itself is the app.