Fast sideways moving objects and/or sideways moving camera are problematic for 24/30 fps. You can clearly see the judder when you follow a fast sideways moving object (or scenery) with your eyes. Heavy motion blur helps a bit, but doesn't solve the problem. Movie directors know this and plan their shots accordingly. In games we don't have similar control over the movement of the camera and the important objects. Judder causes headache. You might not notice it right away, but when you spend hours straight playing a 30 fps game, many of us feel the difference. People are different in this regard. I am personally very sensitive for this.
This problem is even more pronounced in stereo 3d (VR or not). When I first saw the Avatar movie, I immediately noticed that 24 fps was not good enough for stereo 3d. There were several scenes with fast sideways movement. The judder was unbearable. It was impossible to focus your eyes to the flying creatures at all. I am glad that VR makers understood this. The standard frame rate become 90 fps (+ PSVR does 120 Hz timewarp).
There are many game genres where 30 fps just doesn't work at all. All 2.5d games (side scrollers) benefit heavily from 60 fps as the movement is mostly sideways. This includes platformers and fighting games. Just imagine playing Street Fighter or Tekken at 30 fps
I don't understand the point of 30 fps single player campaign vs 60 fps multiplayer in
first person shooters. Why would I prefer worse aim precision and worse reaction time in single player mode? PC gamers are buying 120/144 Hz monitors solely to play first person shooters. It certainly makes the game feel better. This proves that even 60 fps is not enough for this genre. I understand 30 fps for slow paced 3rd person games such as Assassin's Creed or Uncharted, but 30 fps is just a bad trade-off for first person shooters.
2x render time (60 fps -> 30 fps) is not going to bring incredibly better visuals. Next gen consoles tend to bring 8x-10x higher performance. 2x is just 25% of a generation jump. 30 fps is not going to get you anywhere close to next gen visuals. Halving the frame rate hurts the game play much more than the slight improvement in visuals.
It is also worth noting that the recent advances in temporal reprojection techniques favor 60 fps over 30 fps. Higher frame rate makes temporal reprojection work better, as the difference between two frames is smaller. Reprojected data is more correct, resulting in less visual glitches and higher quality. This will result in better quality antialiasing, reflections, AO, etc for the same cost. Or alternatively, you can reach the same quality with reduced cost. As these techniques (and other temporal reuse techniques) advance further, the cost of 60 fps rendering draws closer and closer to 30 fps.