David Dewis :
I hope I haven't misread what you meant, but a £150 GPU can run most games at 1080p 60fps. My £340 R9 290 can run some games at 4k 60fps and certainly can run 1440p at 60fps and 1080p at 120fps. I doubted the ability of the PS4 when it first launched. I don't own one (I have a crossfire R9 290 PC setup) but my brother and my girlfriend do, and I'm impressed by what they can manage. I've read nothing but positive things about things about the 1080p oculus rift, so I'm sure console games that are used to having 720p most of the time wont mind.
The issue is always "at what settings" and "with what games"
The R9 290 is a respectable card, but as you said, it can only push 4K/60 or 1440/60 on SOME games, with SOME settings. Certainly running 2 in xFire helps in that considerably, but consoles do not have that option, and even with the option on PC there are some games and settings where even that amount of hardware is simply not enough. They (consoles) have to be able to play EVERY game at their standard (mid to high) settings, and with low latency in order to pull this off. As found with the Rift, many games are playable at 1080p... but text is still blurry, and other details simply are not good enough at that resolution. So then you are asking hardware that can barely eek out 1080/60 to push out 1440/60? I just don't see that happening any time soon.
The other issue is consistency. Even my good 'ol GTX 570 can play most games acceptably on high settings, with mods, and at 1200p (though having some extra ram would help on newer titles)... but it is merely 'acceptably' which means that we are hitting 60fps most of the time, but when stuff starts happening and the scene gets crazy then it will happily drop down to 30fps for a bit. This is fine and considered normal on a display, but with an immersive headset these sub 60fps dips are unacceptable. Meaning that it not only looks choppy, but can cause nausea and headaches, which is beyond being merely 'not acceptable'. High end GPU tech is getting there... but it is simply not there yet for PCs, and you can forget about it on console where you cannot fit a single $250+ GPU, much less 2 of them.
In other words, hitting these specs some of the time, on some games, with some settings is not good enough. It must hit this spec with all (or at least most) games at good settings, as well as future titles (in the case of consoles 8+ years of new titles), and never drop significantly below that 60fps mark. I am a huge advocate of technology... but GPU tech is simply not here yet even on the higher and more expensive end of the spectrum. It certainly is not here on the budget and console end of things yet. But it will come to PCs in the next 5-10 years... and then to consoles in 10-20 years.
When the tech arrives I will be one of the first to jump on board and enjoy it, but at least for the near future it is (sadly) still a pipe dream.