4k is awesome. Everything looks so crisp ans sharp. You can see more details overall. No surprise if the amount of pixel is increased by 4 times what 1080p has.
I got a 4k TV and 4K monitor. Don't wanna go back. But it's true, 4k eats up a lot of ressources. Even I struggle with some games on 4k like watchdogs 2, kingdom come and FF15.
So, I hope that the next gen of nvidia GPU's will increase the performance much further.

4K is nice - but not as nice for devs when they have to deal with 4x more pixels than previous gen (as opposed to 2.25x they deal with now) while most likely having less gen to gen jump in raw processing power than in 7th to 8th.

So yeah, I'd rather see them focus more on other things rather than 4K native.

I don't care about res, I sometimes play 20+ year old games, just give me smooth framerate and good looking grafix which is always subjective

For current gen yes, but for PS5 and Xbox 2, they will have new marketing jargon probably, like Ray Tracing maybe ??

I just got a 500 dollar 4k HDR Roku TLC tv myself. The upscaling from 1080p to 4k looks quite nice actually, even on my Switch. It make we curious to see what native 4k would look like, but I think I will hold off for the PS5. I would get an X1X, but it feels too late into the gen to pick one up because I will just end up getting launch editions of the next round of consoles like I did for PS4 and Switch. PS4 pro feels like it would not be worth it either because I would want as much power as possible, so if I don't get an X1X I an certainly not getting a PS4 pro either.

Still, I am curious and eager to try native 4k after seeing how suprisingly well the upscaling is. Not bad for a budget TV, but I really have nothing to compare it to either.  If I do not wait till the next wave of consoles  I might jump back into PC gaming if I can afford the initial dip.  At least then I can kind of fiture proof my 4k gaming investment.

OT I do hope they focus more on special effects and performance next gen.  I have already stated many times that resolution is overrated and I still feel that way despite my recent interest in 4k.

I don't know how powerful the next gen will be also waiting for the next nvidia GPU's. But I believe that raytracing will be possible with the gen after next.

What I mean  Ray tracing that is possible in next gen probably some kind of hybrid ray tracing like they have  explained in this year GDC.  It will just fill some spot on object that is difficult using resteration technique and filling it just to add real time environmental effect so developer don't have to focus on building more assets on shadow and reflection, so  more resource will be use  for other affect.  

I like the initial "wow" of 4k content and I'm not really too bothered by framerate issues unless they really effect gameplay. Then again, I often play on my almost decade old HDTVs and it doesn't really detract from the experience.

I guess I'm happy with whatever hardware we get as long as the games make me say "wow".

BTW, if content is bad, 4k could even make it worse.   

I'm sure there is a market but I doubt it is significant enough to put the resources and explore.