Can't be because of the controller because they share the same stuff, and Steam's jukebox destroys swapping discs.
The displays are cheaper ,and better on a PC, and multi monitors for the win.
Sitting 3 feet from a 27 inch 120hz-144hz while you are relaxed in your gaming chair with the headphones on is IMHO way better then couch gaming on a 60 inch screen.
I might have seen your point 5 years ago but not anymore.
Then its the fact the games are half price on PC if you have both console and PC, and you are getting a way better game on the PC most of the time unless it's a shitty ass port.