If the car next to me isn't driven by a person, but is bristling with high resolution cameras that will immediately upload footage of my face to the authorities if I collide with it, I would indeed change my behavior.
They'll be able to correlate across time and space, similar to how phones running Google Maps are reporting their position and velocity to create up to the minute traffic overlays. They'll be able to approach politicians and police forces with a message like "hey, want to get serious about safety? These are the top one hundred drivers in your area who need to be taken off the road now— click through to our portal to find dozens and dozens of videos of each one speeding, weaving, failing to yield, running stop signs, etc."
Each individual incident may be hard to prosecute, but when you have all of them in a bundle, a few a week for months at a time, it'll become impossible not to act on it. When crashes happen, they'll be able to shame the jurisdiction after the fact by publishing dumps of the incidents leading up to it that were not acted on.
https://www.azfamily.com/news/police-say-man-deliberately-ca...
The thing is, that car was far enough away that both cars could have easily turned in front with room to spare. My wife had seen it before starting her turn, and realized there was plenty of time. In fact, after a few seconds, the driver in front of my wife realized just how much time they had, and finally made the turn, still before this other car arrived. Because my wife is an attentive driver this wasn't a problem, but you could certainly see a driver in her position starting to make the turn while looking to the left, and rear-ending the car that suddenly stops for no apparent reason. Of course they would be at fault for doing so, but the first driver's excess of caution, if you want to call it that, would also be a contributing factor.
Sometimes it gets truly absurd. Once I was standing on the sidewalk at an intersection waiting for an Uber when a driver stopped at a green light and started honking at me, furious when I refused to cross the road.
Also, the other day, I was making a left from a one-way street, from the left side of it, and someone tried to drive around me on the shoulder to the left, because they were unaware I was waiting for a jogger pushing a stroller to cross in front of me.
But I generally agree with you. it’s a often egregious and can be extremely dangerous for both the pedestrian and other vehicles when a lone driver stops unexpectedly on a >2 lane road.
Folks that hit the brakes crossing a green light. Braking well before the off ramp so they are going 40 on the highway. Slowing down while merging.
The worst ones are those that are scared to go but decide too late. Like stopping in the middle of the intersection while turning left because there is a car coming from the distance but late enough they end up blocking the left lane going straight.