The boost of being "downtown" isn't so much about living near it but rather overall convenience of getting there and back. So while the ATL stadium is not in a residential area, it is centrally located and the surrounding infrastructure handles the large crowds well. Just being centrally located is huge.
What cities would that be? I have been to every stadium in the East, except Orlando. Only ATL could be considered downtown, and no one lives near it. Plus, despite the hype, it is a crap venue.
In the West, I have been to Dallas, Houston, KC, LA Galaxy, Portland, & Seattle. Only Houston & Portland could be considered downtown. Again, no one lives near them.
I've been to most of the stadiums you listed too and the ones with better attendence seem to have these more convenient locations. The Galaxy don't do that much better than us in attendance on paper (both inflated right?) and don't seem to have an enviable situation.
While I personally agree that it's NBD to ride the PATH to Harrison, it's a barrier for many. You can't strawman that away.