The problem with cars is the geometry. It's just very inefficient for the amount of people you are trying to move. For example, many cars are able to seat four

The problem with cars is the geometry. It's just very inefficient for the amount of people you are trying to move. For example, many cars are able to seat four or more passengers. What frequently happens is that only one person is driving it. You need empty space for maneuvering and ability to stop safely, especially at high speed. If you design for the car, you need to design spaces for cars to park in, which increases distance between places, which worsen alternatives. Coupled with parking minimum and inefficient urban planning, everything is too far apart. Traffic engineer design for convenience of cars with everything else an afterthought. It's either too dangerous or too inconvenient to walk and bike. When you need to drive everywhere, that also increases demand for driving. With cheap land and access to highways, this cause suburban sprawls and of course additional traffic. Given that jobs are found within the city, it's no surprise that we have traffic congestion. Compare people to car, we just need less space in general to move and you don't have the problem of car seating only the driver majority of the time instead of four or five people. So yeah, geometry hates car.