Here’s a better theory: because American public transit is, when compared with the alternatives, not safe, not clean, and not convenient. Take LA, probably the most car-dependent big city in America. Riding the bus or subway in LA is not an enjoyable experience. Nor is it enjoyable to walk around the areas where the stops are. If I were trying to get more people to use public transit, I’d start by making the stations and buses/subways beautiful, clean, safe places that are just nice urban places to hang out in. There’s no need to make it a moral crusade; just offer a better product and more people will use it.
The VTA train smells of pot and the CalTrain often smells of sewage. Periodically there are crazy people yelling on the VTA and regularly there are people having could-have-been-an-email loud conferences calls on CalTrain.
I really like trains and dislike car dependent cities. But it’s hard for me to walk-the-talk when it’s so unpleasant so consistently.