If the goal is full autonomy then people using their phones while the automobile is driving have no impact whatsoever on the accident when that goal is reached,

If the goal is full autonomy then people using their phones while the automobile is driving have no impact whatsoever on the accident when that goal is reached, if laws banning distraction suffice for you to solve problems then your goal is not full autonomy, in which case what's the point of any of it? When full autonomy is reached, I expect that 100% of accidents will occur when passengers are busy letting the car do the driving, so that correlation would be meaningless.