> Passkeys are bigger than that, they're not device bound. That's a really big deal that both Google and Apple have been advertising about their implementations

> Passkeys are bigger than that, they're not device bound. That's a really big deal that both Google and Apple have been advertising about their implementations -- you make a passkey on your phone, lose your phone, buy a new phone, and you get your passkey back. You're interpreting "device" differently than I am, here. Maybe let me use a different word. There's a physical hardware device (the device's "body") and then there's a particular installation of an OS (the device's "soul.") Unlike humans, these device "souls" can leave and come back (restoring from backup) or be reincarnated into a different body (transferring a backup to a new hardware device.) What Apple, Google, etc. are claiming is that passkey credentials are bound to the soul of your device — the unique installation session that resulted in a unique product-key "activation" in their servers — rather than to the body of your device. So wherever the installation goes, the passkeys go along with it. But this does not mean that passkeys are portable between installations. They still inherently represent "devices" — just semantic, abstract devices, that may be incarnated at any given time in zero or one physical hardware devices. And, again, this is exactly how Apple's and Google's own device enrolment for sign-in to their respective cloud accounts works. I have devices listed in my iCloud account that currently have no "incarnated" form — the hardware was wiped, sold, and is now being used by someone else! — but those unique installations do still "exist" and could be "reincarnated", as long as I keep my iCloud Backup of them.