I do not think the idea of banning some vehicles like private cars, trucks and motorcycles for permitting others like bus, bicycles and taxis is actually better than not allowing all vehicles to move. I think we should allow all forms of vehicles in all days in city centers.
Some people think to decrease the traffic we need to ban some vehicles in some specific days.By doing so it becomes very easy and trouble free for people to travel with ease without wasting their valuable times in traffic. But this type of motive has some major draw backs. First not all city centers have similar ratio of people using private transport and private transport vehicles in every days. For example one day family may decide to travel in a car because their family may contain elderly individual or children with physical problem. Or some corporation has send there trucks to go to a the city centers and if those trucks are prevented from going there on that day than business might flap in that day.Trucks can also include water containing trucks or fire servicing trucks. You can’t restrict such important vehicles from travelling to there destination. So having days where you can’t use private cars or trucks can not be very beneficial idea.
Now it is true allowing all forms of vehicles to exist in a road may cause more traffic problems but that is just a problem for road systems instead of problem for specific type of vehicles. One can solve that problem by different way without restricting the type of vehicles that can move.
So end the end I don’t see how preventing some vehicles to move in city centers is a good and beneficial idea instead it shows government is not interested to solving the problems with road system.