Much of the fate adaptions make the mistake of portraying Gilgamesh as a solely bad guy in a sort of traditional black and white way to make things more attractive to people who don't know the original story, which they can't fit into a show since it's too complex. Gilgamesh is the first hero to ever exist and he is very dissapointed with the current world. What people fail to understand is that he doesn't just view the world as his possession, but he views it as an unworthy possession and that is where his sadistic characteristics come from. What's nice about this scene is that all of that is dropped, as Saber is the last thing he still consideres beautiful in the world.