Insomniac didn't have a lot of PC releases in the first place, Housemaque's track record was spotty at best and Nixxies is more of a porting studio. You have a much better chance of seeing Insomniac and Housemarque projects coming to PC today than you did three years ago. Further, none of those studios are self publishers. Given the autonomy that Sony is affording Bungie with their acquisition, I doubt another acquisition of such scale, say Capcom, would be much different. Sony and Microsoft's strategies are different and Microsoft's pockets are much deeper. Sony is going to look for quicker return on investments and disrupting a publishing strategy would be counter to their goals. If they want to go exclusive shopping, they'll look at more studios like Insomniac, Remedy for example.
While their strategies are different, both Microsoft and Sony are looking far beyond selling you hardware. There is little profit in hardware.