Modern traffic controllers would probably get run over all the time because they and half the drivers would be looking at their phone too much :-)
Discussion
I guess then protection systems would have to be built. More building, inspecting, maintaining.
Plus more restrictive traffic speed and flow controls could be put in place.
This idea just keeps getting better.
Nah, we need a person that can hold the traffic controllers phone and when you go for a drive you give your phone to a person who will then follow you to your destination to give you back your phone.