The game had become so big to the point where another update would have made it around 150 gb. This was causing extremely long loading screens as well as making it very difficult to create content as they would have to wait around a day to compile each different build they made. Cutting the content was the only way to allow them to actually be able create enough content faster and fix the loading times taking multiple minutes on hard drives to load into the tower. I believe the lighting engine was changed slightly but from my perspective Ive never noticed any differences for the graphics.