In practice, they either use system authentication if you use the implementation bundled with iOS/Android - and sure, that can be Face ID if setup, or other forms of biometric authentication. Both operating systems have APIs that allow password managers to provide their own implementation of passkeys, and in that case you have to authenticate with your password manager - sure most of them support using system authentication (biometrics) as well, but this could also be a master password or hardware key (which work very similar to passkeys by the way).
I’d argue if you don’t assume that whatever system you’re using is reasonably secure/private, you probably shouldn’t enter any passwords on that system either. This isn’t a passkeys vs. passwords problem.
X2 “Elite Extreme” probably in ideal conditions vs. the base M4 chip in a real-world device. Sure, nice single core results but Apple will likely counter with the M5 (the A19 Pro already reaches around 4,000 and the M chips can probably clock a bit higher). And the M4 Pro and Max already score as high or higher in multi-core. Real world in a 14 inch laptop.
It doesn’t “crush” the M4 series at all and we’ll see how it’ll perform in a comparable power/thermal envelope.
I don’t hate what Qualcomm is doing here, but these chips only work properly under Windows and the Windows app ecosystem still hasn’t embraced ARM all that much, and from what I’ve heard Windows’ x64 to ARM translation layer is not as good as Rosetta 2. Linux support is pretty horrible, especially at launch.