Relays and clients are already storing everyone's kind 0 events, so why not just use them
I'll add gossip model https://bountsr.org/gossip-model/
Nip65 is a bit weird, I don't understand the rationale of not using kind 0 events. https://github.com/nostr-protocol/nips/blob/master/65.md#why-not-in-kind-0-metadata
But might still add support for it
Discussion
Perhaps because it’s only the relays the user is explicitly connected to that are storing their kind 0 events, whereas in the NIP-65/Gossip model, this list of relay metadata would be sent to hundreds of relays who may not want to deal with moderating the other things in kind 0, like profile pics or bios? Not sure