Every game has different needs depending on what that specific game's developer desires of it. Simply put, a game like say GTA where there's a lot of shyt going on requires a certain amount of grunt to deliver 4K. The dev can choose to make the graphics lower quality or lessen the scope of the game to achieve 4K but then people will complain that the "graphics look booty". If they hit 4K, then they gotta worry about the performance of the game.Okay that's fine but why aren't they just making games that are native 4K? what's the hold up?
If the performance isn't mostly to rock solid, then those very same people gonna be bytching about how this new hardware can't hold 30fps completely disregarding that the game is also pushing 8 million pixels just to look the part.