Ford, like GM, has a literal camera monitoring the driver's face so they can see if they are paying attention. Seeing what your face is doing is a much more reliable system of measuring attention than whether or not the driver is touching the steering wheel while reading their book.
Last year they pushed an update to use the built-in cabin camera installed in 2021+ cars for "driver attentiveness."
Compared to Ford and Cadillac's IR-illuminated driver attentiveness cameras pointed straight at your eyeballs and can see through sunglasses and works in the dark, the wide-angle cabin camera may not even see your face if you wear a hat, certainly _does not_ have a clear view of your pupils, and doesn't work in the dark or if you have dark glasses on.
Tesla's isn't good enough to replace wheel torque as an attention monitor, and they don't even pretend to (still requires wheel torque to keep FSD/autopilot enganged.)
In particular, it has terrible night vision and no IR illumination so it can't see you well enough at night to work.