I suspect individual vehicles is inherently inconvenient. The parking lot for Disneyland is an example, the traffic jams of any city with over 50k people in it are examples. Individual vehicles do not scale very well, and through extreme expense the US has built infrastructure to make individual vehicles as convenient as can be.
> not because they prefer it.
I would like to see data behind this. Driving for a commute is generally not enjoyable, it's time a person will not get back and meanwhile they have done very little productive other than perhaps listen to a podcast. OTOH when on a bus, someone else is worrying about the roads and plenty of people get significant work done, reading done, generally relax. I suspect most would prefer mass transit if it were more time efficient. Driving yourself is still a pretty killer option in most of the US as it's an extreme reduction in commute time due to lack of density and frequency in the mass transit network.
*To clarify, the typical bus experience in the US can vary quite a bit. I commuted into Seattle for several years on the bus system. That is my experience, those trips were 99.9% fine experiences, it was quiet and essentially everyone was just messing around on their smart phones. The only really unpleasant part of the bus experience was there were not enough of them running such that the bus could be crowded and was a long wait between buses. That is a different experience for sure from the buses that run within downtown and riding those buses around 2pm when there are no commuters on them.
My claim is that a well funded bus system is intrinsically more enjoyable for the same reason an AV is - because you can do something other than 'driving' while traveling.