The bitcoin pubkey and nostr pubkeys are similar. All nostr users have a native bitcoin address.
Wow .. can any Bitcoin wallet hold against my nostr npub ?
Or a more appropriate question is - can I nostr with my btc keys ? .. if so , then every btc wallet already has a nostr account .. This is a big deal - which means nostr has millions of dormant users who just need to be activated .. they just need to claim their accounts ..