The NIP on attestations that nostr:nprofile1qqsvfa085adgecmg84ffelcxx6zrn3ffu5jrc6cjtwng0zge3ptv43cpz9mhxue69uhkummnw3ezuamfdejj7qgcwaehxw309anxjmr5v4ezumn0wd68ytnhd9hx2tcwmah2e developed addresses this issue. Originally for proof of place but has been generalized. Ultimately you have to trust the attestor.