The map is a little misleading, only in the sense that people care a ton about the difference from 0-1 hour, but no one commutes 5 hours. So we get a map that gives a ton visual weight to "commutes" more than two hours. I know I'm the one making this about commutes, but they are concerned with rush hour, so I don't feel like I'm out of bounds.

The fact that all the cities look the same speaks to this fact. The only restriction seems to be geography/geology.