I have predicted this for years. I think they will make city cores self-driving cars only, with no other cars, or even bicycles because they are too chaotic. China should have done this with those ghost cities, so that they could have dominated with full self driving before other countries.

Someone will own the platform that coordinate car movement, and then all cars will need to pay to get onto this coordination platform that will tell each car how to drive, which route to take, etc. Each car know what all the other cars in its area will be doing, so that mass coordination is possible. This is how you can get a completely full highway but all traveling at 65 mph 1 feet away from each other.