Americans own cars because most of them live in single-family houses on large plots of land, and that doesn't make public transit for daily commuting a realistic possibility. In Paris car ownership is very low, maybe 1/3 of adults, but in rural France the car ownership rate is easily 95%+. I haven't seen a single developed area in the world that has violated the rule that low density = high car ownership and vice versa.
The other rule that I have never seen violated is that the large majority of middle and upper income people do not want to live near low income people, due to crime or other reasons. In Europe, poor people live in the suburbs, so the middle income live in the city with high density housing. In the US and some other places (south asia), low income people live near the business center, so the middle income live in low density housing in the suburbs. These are for historical reasons and cannot be easily changed.
The real reason Americans own cars is because we’re rich enough to afford a more expensive and more convenient system. Public Transit at scale is surprisingly cheap when compared to all the costs associated with car ownership * 10’s of thousands of people in even a fairly small community.
Are we? When you zoom in on things like road maintenance backlogs and auto loan delinquencies, it kind of seems like we are not rich enough but have been pretending to be.
The delinquencies are the ones you hear about. What doesn't get reported, statistically, is when people are balancing absolutely everything in their life on a knife's edge to fit the car in with all their other expenses when they are living on a meager salary (or unemployed).
And that is only on the private individual's side. Costing out car-dependent development in terms of building and maintaining roads, bridges, power lines, water pipes, trash collection, wastewater treatment, fire, police is all monstrously expensive, and it is one reason why when the roads get damaged from use and need repair, they get chronically backlogged and problems keep mounting for years and years.
One thing people notice about Japan and the Netherlands is how immaculately maintained the roads are. They are significantly more pleasant places to drive, specifically because they did not overbuild road infrastructure.