For decent-looking games at playable frame-rates, the PS4's hardware will never be able to render anything above 1080p. It simply isn't powerful enough for anything even close to 4K, and honestly, that's not all that much of an issue.
In fact, the most that its graphics hardware can physically output through the display connectors is 2560x1600. So don't bother even arguing about this; the rendering technology is not yet available, the display technologies are not yet widespread enough to make it feasible, and anyone who says that the PS4 is powerful to handle a graphically intensive or "realistic" game at a resolution even close to 4K is a complete idiot.
Don't bother embarrassing yourselves with psuedo-intellectual techno-babble in front of people who actually know what they're talking about.
And don't ever compare the PS4's GPU to a GTX Titan.