>Public transit enables higher density, (...) pushing rich and poor people closer together.
The later doesn't follow from the former - there's nothing about public transport that inherently clusters the affluent around it. Good schools & "nice" neighborhoods would be an overriding concern.
Private transport enables[1] mixing and matching, by the virtue of being rather flexible and quick to react to changes in supply & demand. There's nothing inherent in private transport that would cause self-segregation, nor that would allow planned segregation. Your point about density holds true, but it's still a low-density somewhat homogeneous society.
Public transport, by the vice of being mostly fixed in place and centrally managed, is how one channels people into pre-defined paths and spaces. Sure, higher density is possible, but enclaves of the reliant are created around the transportation hubs, while the affluent can settle anywhere - presumably with no unseemly bus stops & metro rails in view.
Build a bus or metro rail stop, who do you think will tend to settle around it?
Have you ever been to a an actual city in your life? The most affluent neighborhoods are the ones with excellent transit. Look at downtown and midtown Manhattan.
The later doesn't follow from the former - there's nothing about public transport that inherently clusters the affluent around it. Good schools & "nice" neighborhoods would be an overriding concern.
Private transport enables[1] mixing and matching, by the virtue of being rather flexible and quick to react to changes in supply & demand. There's nothing inherent in private transport that would cause self-segregation, nor that would allow planned segregation. Your point about density holds true, but it's still a low-density somewhat homogeneous society.
Public transport, by the vice of being mostly fixed in place and centrally managed, is how one channels people into pre-defined paths and spaces. Sure, higher density is possible, but enclaves of the reliant are created around the transportation hubs, while the affluent can settle anywhere - presumably with no unseemly bus stops & metro rails in view.
Build a bus or metro rail stop, who do you think will tend to settle around it?
[1] does not force, but enables none the less.