> The worst thing that happens is the sensor breaks and then they become manual headlights...

Don't be too quick to disregard automation dependency. I agree that a headlight switch is probably quite low-risk, but every action you automate carries the risk of overloading the operator if it fails at the wrong time.

Even two decades later, I find the 'Children of Magenta' talk highly illuminating. Maybe you'll find it interesting as well: https://www.youtube.com/watch?v=pN41LvuSz10