I think it's down to hardware limitation in AW's case. If you take Rememdy, a self proclaimed highly technical development team, who's spent 5 years working on the engine and you would think they have exhausted every options available for the game but still ended with a 540p buffer. It's pretty clear to me now the incredible lighting and shadows of AW is the double edged sword for which most devs have been trying to avoid. I think there's a reason you don't see that many 540p games.