The thing is, besides Mortal Kombat, they are not actually getting that many franchises, unless they plan to reboot abunch of defunct Midway IP. Batman and lego are licenced properties. By buying publishers MS is opening pandoras box here with repercussions. Sony doesnt have as much cash on hand but they have enough to go after a major publisher if they needed to, same with nintendo.
This reads like fanboy wishful thinking. Major publishers aren't randomly up for bids, and most if not all of them are too large for acquisition or owned by a parent company.