You don’t get to be a billionaire without some malfeasance.
And even if you don’t assume actively malicious intent like you should with Musk, there’s a lot of potential danger with technology like this, and if you don’t stand a lot to gain, and have reasonable controls against things going wrong, it’s probably not a good idea to be an early adopter. It’s just like a pacemaker, there are a narrow segment of people who should want to test a new model/concept for them.
Speed cameras are a privacy issue that doesn’t solve the problem of speeding. People are most comfortable driving the speed the road is designed for, and if that speed is too high, the solution is to modify the road for a safer speed. The speeders in your example are right here, for the wrong reason; speed cameras should be rare if they’re allowed to exist at all. They have, at most, a short term benefit, and broad public surveillance is a very serious issue they contribute to.
“if I randomly stop in the middle of the road so another car can get in, the car right behind me probably won’t hit me”
Honestly? Especially if it was only for cops