Depleting oil reserves are quickly forcing this change.
I'd take "medium" density any day though. Enough density so people don't need to move miles daily, not enough density so people can't afford some healthy living space. NYC and SanFran are way over the top.
Agree, probably your "american style medium density" is what I would consider "low-ish density", healthy and pleasant too...
...but using the "depleting oil reserves" and other eco arguments to make people leave in what I see as much lower quality conditions is inhumane and cruel in my pov - just build good quality public transportation, make it electrical (even trains are efficient) and go all nuclear to power it all, putting up with all the eco-consequences of it ...or maybe Elon Musk's Hyperloop will redeem everything :)
I'd take "medium" density any day though. Enough density so people don't need to move miles daily, not enough density so people can't afford some healthy living space. NYC and SanFran are way over the top.