> to claim that this is a meaningful restriction feels wrong on many levels.

You must be joking. Requiring me to have a technology in my car that can apply the brakes without any input from me and without warning? That is most definitely a meaningful restriction. You're forcing me to trust the government's estimate of the relative risk vs. benefit. To be blunt, the government sucks compared to me at estimating my relative risk and benefit. Plus, government institutions have repeatedly shown that they will lie to me about such things to serve political ends. So no, not buying it.

> I'm restricted such that I have to wear seatbelts. I can't buy a new car without rear view camera. I can't buy a new car without antilock brakes. Headlights. Brake lights. I could go for a long time on this list. Are you claiming none of those make driving safer?

The question is not whether these things make driving safer as compared to not having them.

The question is whether the government regulations we have, which include requiring these things but also include lots of other regulations that have far worse justifications (if they even have justifications at all and aren't just blatant attempts to extort the public, such as speed traps), are a better system, on net, than a system in which such things were a matter of voluntary choice, but we forced people to bear the consequences of their bad choices. Oh, you weren't wearing a seat belt and you got in an accident? Sorry, your insurance company will not cover the medical costs due to injuries you suffered that the seat belt would have prevented (or you have a much higher deductible in such a case). Oh, you hit something while backing up and you didn't put a rear view camera in your car? Same sort of answer from your insurance company. Oh, you hit something because you didn't have anti-lock brakes and so you couldn't steer to avoid the collision? Same answer.

In other words, if it is in fact true that these various technologies reduce the risk of accidents, then people who know they will have to take the consequences if they cause an accident will use these technologies to reduce that risk. But in our present regime, our society appears to be violently allergic to such things. The very existence of no fault auto insurance, for example, indicates that we don't like the idea of having to take the consequences of bad choices--but the result is that everyone pays more for auto insurance (IIRC, average rates in no fault states are about twice what they are in states that don't have no fault).

We would all be better off if we abandoned the idea that government regulation can magically protect people from bad consequences. We would also all be better off if we abandoned the idea that we can somehow magically have a government that only makes good regulations, and accepted the inconvenient truth that government regulations come as a package, which even if it contains some good regulations contains many more bad ones, and all things considered is a net cost to us all, not a net gain. We need to stop depending on the nanny state to protect us and be responsible adults who are capable of judging risks and acting accordingly.