Guys, this is recommended specs. No different than PC gaming in general.
For general PC games, you can build a mid-range PC and play most games, but maybe you have to dial down quality to play the very latest games, while keeping details up, for a lot of other games. The flexibility is a big advantage of PC gaming.
Now for VR, the bar is higher. So it means that a normal mid-range PC gaming, becomes the bare minimum VR PC. The recommended 970 means you'll get the best experience. Doesn't mean you can't get away with something cheaper. Sure, maybe you'll have to cross a few more graphically intensive games from your list and maybe lower details to bare minimum to get acceptable FPS, maybe you'll have to play at under 90fps, but again, it's just the nature of PC gaming ...
Now, with Morpheus, no matter what, PS4 hardware is more less capable than PC for VR. I own a PS4 for MP games (play with friends) and a PC for single player games. I also own DK1 and DK2. I'm skeptical that Morpheus will be able to satisfy my VR needs. Great looking games look average to poor in VR just by spreading pixels over 100 degrees FOV. I'm skeptical that games on Morpheus will look decent, based on my experience with DK1 and DK2. I hope I'm wrong, and I keep hoping Morpheus delivers, so it's my SP and MP VR platform of choice! But the Rift (or Vive) is my safety net. These three are competing and I plan to support whoever does it right to bring VR to success. Possibly support 2 out of 3.