> is if you're bad at designing cities for it

Consider that the transportation system might not be the best fit if it requires designing the rest of the world differently and against preferences (large, detached, single-family homes with a yard).

Those preferences are based at least partially on the available transportation. If the automobile didn't exist, would people still prefer to live so far from jobs and entertainment?

We also have the issue that dense inner cities are subsidizing the infrastructure for the spread out suburbs. If people had to pay the full cost they again might choose differently.