I was told that the skyscrapers were restricted so as not to obscure the view of the mountains. I am not big on “nature”, but I like a city trying to pay respect to the character of its terrain.
Also, skyscrapers create traffic issues. Phoenix has big city traffic, but nowhere near as bad as Atlanta, Chicago or DC. In fact, it is better often at rush hour even than some small cities like Hartford, and Madison (whose lake makes it impossible to use alternate routes).
People complain about sprawl, but the only alternatives to sprawl are building up (NYC, Chicago), pricing people out of your city (SF), or stagnation and decay (Detroit, Cleveland).
One of the other alternatives to sprawl is not letting a lot of people in from other countries.
Yes, I remember them saying the skyscrapers were restricted in height so as not to obscure the view of the mountains.