I agree but it's an interesting problem, things like parking spaces and roads will still have to be made to the size of largest vehicle that will use them and I imagine more cars in the same amount of road will lead to even more traffic.
In Europe, if you're driving a huge North American truck (which some people do) your parking options are very very limited. We don't build everything for their sizes only because there's some of them on the road.
And the change will probably not increase the amount of cars on the road, because at the same time, bikes and public transport are becoming more attractive in cities all across the continent.