Well, the further away from a assumed central point you get, the larger the area gets that you need to cover. Doing this with busses usually leeds to crazy zig-zagging routes which take a ridiculous long driving time - much longer than you would need in a own car.
The best way to get rid commuter traffic would be to spread out the typical destinations people want to go to. Like places to work at, do shopping, and the usual life activities. Best up to a point, that you can do most journeys with a bicycle or so. That would be a win in different ways - for the environment, for city developement, for your own bank account ect.
But not for the car sales, and the whole industry that is connected to the use of cars.