They don't own cars because owning a car in the city sucks in a lot of ways, more so than in rural areas.
So yeah, if your point is that if you take away all the bad parts of using a car, and leave public transit as is, then using a car comes out ahead. Splendid.
That feels like you've made a tautology here. In places where public transit is more convenient than driving (and parking), many people choose not to own and drive a car.