Thinking of a way to reduce the numbers of vehicles at use especially for private individuals is something that can be achieved though before passing such policy the government have to first put in place adequate public transportation system with easy access for the people because majority of people opt for private means of transportation due to inadequate public transportation system especially in developing countries.

Regulating the amount of cars and expecting people to travel with public cars is literally impossible for the rich. These public terminals have low security and it takes a lot of time with lots of people breathing the same air in an enclosed car. Not many rich people can survive in such environments. A rich man is an easy target for kidnappers, so, going public is not adviceable.