Then you don't get the strong phising protection though. One of the reasons U2F/webauthn is great at phising protection is that the key verifies the sites domai

Then you don't get the strong phising protection though. One of the reasons U2F/webauthn is great at phising protection is that the key verifies the sites domain. IIRC there has only been one good attack against that and even that required the user to allow webUSB for the phising site (and it has been patched).