If they released their stuff on PC they'd probably get money from me.
Currently they get zero from me as I have no interest in consoles at all and don't plan to purchase one.
The money they would see from people like you who would pick up a couple of their games (possibly even on a Steam sale) is nowhere near as valuable as the money they receive from people like me, who did purchase their console, and numerous of their games for it. I already have a PC, and certainly would not have bought an Xbox One (or Xbox Live, which I've now had for a decade) if my PC offered all of the games their consoles do. The math just doesn't work out.
That's not even considering the number of people that buy only an Xbox and not a Playstation, who would by the Playstation instead of becoming PC gamers.