I think, when Console reach 980ti graphics, that is the point where people will quit computer gaming..
You really don't need much more power than that for 1080p..
4k Gaming is far away even for modern PCs..
Let me play devils advocate for a moment and let us enter a universe where consoles were on equal hardware footing with high end PC's upon release. People still would not quit PC gaming because...
1. Far more Games and exclusive games on PC.
2. EVen if/when consoles even match high end PC's, PC's evolve and can be upgraded so one new GPU release later and the PC is already leaps ahead again
3. 1080P won't be mainstream forever,4k may be awhile away 1440P is not.
4. PC has numerous other advantages over potato boxes besides just power...just a small handful of which being..
A. EMulators
B. Backwards compatibility
C. Not having to pay to play online
D. Entire genres consoles don't have at all or barely have with only a few games of RTS,MOBA's,MMORPG's,Flight sims etc
E. Not having to use a controller which is very imprecise in games like FPS,but having the freedom to use everything on PC.
F. When 1440P pushes over 1080P as the#1 resolution chances are consoles will be where they are now Framerate wise IE many games running at 30 FPS some dipping below that.
G. Multi monitor setups
H. Cheaper costs of ownership over time due to cheaper games,free online play
I. Mods
J. Much longer warranties on a self built PC than a measly one year on a console. My shortest warrantied part inside my PC is 3 years
K. Higher FOV
L. I won't void my warranties by opening up and cleaning my PC like i will with a console
M. Much stronger Indie game scene on PC leading to many more game experiences consoles will never see
These are just a small handful of reasons even IF consoles released with the power of a GTX 980 PC's still have many many other advantages over consoles as a whole i could very likely and easily list a reason for every letter of the alphabet but it's 4 AM here
PC gaming isn't thriving due to being more powerful as most of the mainstream PC gamers aren't running super high end hardware the most popular selling cards are usually Middle tier and most people are running hardware 2-3-4 years or older. It's thriving because of it's inherent numerous other advantages over consoles.