You have proof of continued identity with nostr thanks to the keys but you still have the challenges around linking keys to people which were a major struggle for GPG. The solutions for that tend to involve social media or DNS (checking a personal domain).

This seems like a good area to improve since things like code signing could also benefit. One of the big problems I see is bootstrapping your network initially and also solving the lost phone problem without setting up a system which phishers and spammers would have a field day with.