Picture it. Gondola cables. A multistory tower at Disney's Coronado Springs Resort. A multistory DVC tower at Disney's Caribbean Beach Resort. So much for looking up and seeing tall trees and the Florida sky.
That's just reality. When you keep growing, you either sprawl out or build up. It's what every rural to suburban to urban center has to deal with.
Yes, WDW still has a lot of land to spread out on, but it's not infinite. And as much as they attempt to spread, human population will outstrip the growth.
If you were sold on the dream of seeing only tree tops forever... you were being a bit uncritical and naive.