As opposed to where you store your passwords? I can only speak for me, but they're in 1Password; if the police get my phone, the same thing protects 1Password as would protect these passkey private keys: FaceID, maybe a PIN if a lockout can be triggered before they get it, and at its core, the Secure Enclave. There's no legal advantage to passwords, unless you were actually memorizing every password you've got (and if that's the case, son we got bigger fish to fry).

A ton of people in our bubble have this Mission Impossible-esque view of their security footprint, which simply isn't true in reality. Its XKCD 538 every time this comes up.