There are a lot of factors that push against and huge, revelatory changes in PC graphics technology that will provide immediate, tangible results to the PC gamer.
Prof. Morgan McGuire buy csgo skin of Williams College, an industry consultant and coauthor of “Computer Graphics: Principles & Practice", explained that, “We'll quickly see a few small improvements to a small number of games, but DX12 won't instantly make everything better — it is a developer technology, not a consumer one. Over the next two years we'll see the real impact as new PC-exclusive games designed for DX12 ship.”
That’s another important point about DirectX 12: the benefits it confers, it confers on developers. And the nature of game development, as Gaslamp Games’ programmer Nicholas Vining pointed out, is "as soon as you get a game running at 60 FPS, your designers and artists will immediately knock it back down to 30 FPS."