The problem is that the US have relatively few cities proper, in the European meaning of the word. If you live in NYC, most of the time you don't need a car, and a ton of people here don't even own one. If you look at, say, Houston, it's a whole different business.
It's definitely better than America but I think that's an overly rosy view of European cities. Yes the capitals and a handful of the biggest cities are like that, but most of the minor cities have poor enough public transport that a car is still close to a necessity for most of their population.
I live in Germany and even minor cities that probably nobody outside Germany even knows about (like Brandenburg an der Havel, Magdeburg and Halle) have very decent public transit to the point that you don't really need a car to live in any of these.
