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.
Yes they do. US public transit is terrible and various groups like Strong Towns describe this and explain why. Things like the way buses wind-up the first thing cut in budget crises etc are important parts of the barrier to ending a car-based urbanism.
See a multitude of article here: https://www.strongtowns.org/journal/category/Public+Transit
I've noted that public transit is unpleasant 'cause it's underfunded and poorly planned. There's not much money for security, the routes are bad and irregular and so only those with no other choice ride it and so it's the very poor and that can result in bad behavior - plus those aiming to victimize step in as well.