> However, I've long thought that motor vehicles should have some kind of black box that monitors various driving metrics such as how "smooth" the driving is. This could provide valuable data to insurance companies and they should provide a sizable discount for drivers who agree to provide that data and have good driving scores.

This has been available for years from some insurance companies.

There’s no reason it needs to be built into the car or to automatically report it against the driver’s will. It’s an opt-in thing.

My coworker got it when they first came out because she thought she was a safe driver and wanted a discount. She got a monthly report of how many sudden stops it recorded and the number was much higher than she would have guessed. She never could figure out what was triggering it, but began to suspect it was the stop signs between her house and the office. So instead of coming to a complete stop she started slowing down and then rolling through (which isn’t legal in our state). Unintended consequences strike again.