I'd hesitate to bash Uni for their use of 3D simulators without acknowledging that Disney's newest headliner is a 3D simulator. With that said, Disney has been smarter about their implementation, spreading them between physical rides over longer stretches of time.
Simulators aren't inherently bad; I just got off Flight of Passage a few hours ago, and my initial thoughts on the attraction are that it's the best ride in Orlando and that they figured out how to reinvent the simulator into something more than the sum of its parts.
Uni's problem is not screens; it's that they don't use them in creative ways. Disney's is, of course, economic efficiency and pulling a full experience out of smaller budgets, but in Avatar's case, they built a land that's actually worth what it cost (based on my own personal experience today).