I consider NIP-05s from certain relays to be higher trust, so our people search checks those lists, first.
You don't have to add the NIP-05 to your profile, for this to work, as we look at the server's own list.
Discussion
FYI the nostr.json file returns an empty response if you don’t pass in a name but I can make something that can check if certain public keys have a higher trust level and how much at NL.
I think I always pass in a name.
you have to generate specific responses from a name or otherwise by the spec you should return the whole file with all the names.
my personal NIP-05 just serves only the whole thing, i haven't bothered to write in the ability to do more because my reverse proxy, which serves it, hasn't got a database to generate only one username reference (i know it's simple, but still). also just to point out, but the name _ can mean a domain/subdomain without an @. you can also do this, instead of username@domain if you have a wildcard domain that lets you listen out for the subdomain as the signifier.
Not all NIP-05 providers are the same. Some will give you an identity for free without any requirements, some only ask for a few sats, while others hand-pick real Nostriches with quality content or offer NIP-05 only to people they know in real life. Because of that, I proposed NIP-85 to create chains or webs of trust between identity providers: https://github.com/nostr-protocol/nips/pull/1210 It's pretty cumbersome, but I believe we need to find a way to treat NIP-05s differently based on trust; otherwise, NIP-05 would be almost meaningless.
Nostr identity and social graph are untouchable, you have them and you have full control. On the other hand, NIP-05 or attestations can be stripped by the NIP-05 provider.