Almost none of the European city has a flat/grid structure as typical of more 'recent' American cities, yet they most have a much better public transit story, so I doubt that's a factor by itself.

More likely, that's correlated with something else that is the real explanatory variable (history, etc...). John Kay had a good article on a similar topic: http://www.johnkay.com/2013/01/16/london%E2%80%99s-rise-from...