And how many Americans live in places without any public transport?

As a European I spend some time in LA and Las Vegas and while not optimal I could get everywhere without a car. I could even do a day-trip to Bakersfield by bus.

Your anecdata to this one time you took a trip to California doesn’t help.

You can just look at % of urban residents that use transit, which is lower in US than any western country. Clearly transit isn’t built or available in a sufficient way to majority of people