[e-topy]

Apple's Face ID uses what is essentially a 3D camera, a simple 2D color camera cannot compare to that in terms of accuracy.

[lozenge]

Windows also uses infrared LEDs to light your face and prevent a flat photo from being recognised as a face.

[throwaway889900]

Windows is an operating system and does not have dependence on specific hardware being present.

[crowcroft]

Apple has clearly done a lot of work in this space and have decided to retain Touch ID on Macbooks. I think this is fairly instructive.

[real0mar]

That was primarily because the face id sensor stack is too thick to fit in the laptop lid

[aniviacat]

AFAIK Pixel phones, including the Pixel 9, only use 2D images for face unlock. So it's definitely possible to reach mainstream quality with conventional cameras.

(Unless you'd argue that the face unlock found on Pixels is not passable either)

[MengerSponge]

I don't know how Google does it, but it's possible to extract 3d information from a 2d sensor. You either need a variable focus or phase detection in the sensor.