Nostr may still be somewhat vulnerable to DSA censorship enforcement. Relays are few. They are identifiable and can be doxxed to ownership, which can be targeted by law. They rely on public DNS, domain registrars, and CAs for TLS certificates. These can be attacked by law enforcement. Not nearly unstoppable and ungovernable enough to survive.
Discussion
Nostr may still be vulnerable to governments such as EU enforcing DSA.
Idea: possible to develop a self-contained Nostr client and relay that combine both functions, so Nostr becomes a hybrid of relays and p2p?