No, the idea that this is only possible in dense cities is a myth. Look at the town planning of small rural communities in the US established before the dominance of cars. They are way more walkable and bikable than most modern developments. People living in small towns probably still need to own a car, but they don’t need to use one nearly as much.

This artificial division between super high density cities where public transportation is possible and super low density suburbs where you must have a car is also a very North American mindset. There are small towns and villages throughout Europe and Asia serviced by buses and trains, and with plenty of biking and pedestrian infrastructure. Cars aren’t inevitable, we just seem to be unable or unwilling to imagine anything else.