Actually the government DID try to do this. The U.S. DOT had an entire decades long program researching the following:
1) Costs and plans for updating roads with sensors
2) Upgrading traffic boxes (the things that control traffic lights and such) with a module to communicate back and forth with surround cars
2) Forcing manufacturers to install a module in all cars that would allow them to communicate with surrounding cars + road sensors + traffic boxes.
The problem was the amount of push back the government got from car companies was really absurd. And of course Republican funding games. Republicans love their private companies so they basically sapped the program's funds.
It was able to pick up momentum again from around 2012 onward though:
* https://www.its.dot.gov/about/federal_its_program.htm
* https://www.its.dot.gov/research_areas/automation.htm
* A practical example of its research: https://www.its.dot.gov/pilots/florida_agencies.htm
Of course that would require centralization and working with the government. The government has no incentive to do this because it would just create another problem for them (mass unemployment).