I play my pc on my couch. U guys will be forever on this 2005 loop.
I think its just a bit more complicated for most people to figure out how to hook up a PC to a "TV" which I persnoally see as large PC monitors anyway.
Is it that complicated to plug in an HDMI from a PC into a "TV" and connect a controller? No, its rather easy, but I think all about perspective.
The thing you can't do from a couch is use mouse and key for certain types of games, like FPS for example, where you need better posture and stable set up.
With a PC you have best of both worlds really, since you can choose your preferred input method.