In reality, most Americans live in cities and suburbs, concentrated on the costs and in the Midwest, with urbanization only increasing over time.
In other words, most people in the US already live in areas where there is sufficient density and short enough distances to live in a place where maybe you need to own a car but you shouldn't necessarily need to use the car for every type of trip.
There are suburban designs emphasizing single family homes that can still accommodate a lifestyle that isn't using a car for every type of trip, but North America has simply not developed that way.
Development in North America goes wildly beyond just accommodating cars, it instead actively designs in hostility toward pedestrians, cyclists, and generally having the chance of using anything but a car for getting around. Features like:
- Winding suburban developments separate themselves from the main street grid to eliminate thru traffic, but that also makes walking/cycling out of the development impractical by extending travel distance
- Stroads [1] and big box developments make it unsafe/impossible/impractical to walk to businesses that are right next door or otherwise in the same development, never mind crossing the actual street.
- Transit system design and schedules that emphasize downtown travel during bankers hours.
[1] https://www.strongtowns.org/journal/2018/3/1/whats-a-stroad-...