Or game on a monitor (as some ppl with consoles do) I dont use consoles but playing an RTS,RPGs etc at 2048p vs (1080p or 1440p) is a massive visual difference. Sure with fast paced FPS's etc you mightnt see much of a difference but slow paced games you do.I honestly think 4K is far too soon for gaming, to notice the difference you'd have to be sitting either far too close to the TV or have a stupidly large TV.
Esp if the game lets you see more of the game area (and not just shows the same area with greater detail)