The US cities with the best transit have poor transit by world measures. Sure, most people don't live in the city centers, they live in the suburbs. But for much of Europe, suburbia means easy access to high frequency regional rail transit systems that gives you easy 45-60 minute access to city center at all times of the day. Even in the US, where I've lived in cities that had what the US thinks is good transit, getting to an intercity rail station has often been as easy, if not easier, than getting to the airport, even though I'm originating in the suburbs.