The ridiculous expense of upgrading is only one of the factors. The troubleshooting and tweaking and fiddling involved with PC gaming is just awful. "Ok, I got the latest video card, I'm all set. Oh wait, my system is rebooting because I need a bigger power supply, so I'll get one. Oh no, the power supply I got has a lot of watts but not enough power on the 12 volt rail! Ok, so I got a different power supply but now the game I wanted to play crashes because it's not compatible with the drivers for this video card!" AAAAGH I JUST WANT TO PLAY A STUPID GAME ON MY BIG ELECTRONIC TOY.
Compared to a console, where for the most part, you put the disc in and it works. Sure I can't upgrade the video card and then enable the developer console so I can manually tweak the settings for three hours to maximize framerate instead of actually playing it, but I think I'll be ok.
Going back to PC gaming after not gaming and then playing on consoles for a while has been like going back to an abusive, high-maintenance relationship. Except guys in crappy relationships usually don't accuse other guys with really good girlfriends of having "dumbed-down relationships."