Microsoft is a western company. They just bought a bunch of western devs. They're clearly going for that market, or Japanese devs are too smart and protective of their IPs to sell to stupid westerners. Starcraft is super popular in Korea, but other than that they have a bunch of FPS and western RPGs.
Sony is a Japanese company which also has a huge global presence both on the consumer level but also on the business level. They will keep that Japanese "mainstream" market going. Did Microsoft manage to buy From Software, or SquareEnix, or Capcom, or even smaller companies that have diehard fans like ArcSys or SNK? These super Japanese devs will likely never sell to westerners, Japanese people just don't do business that way historically.
Nintendo is a Japanese company that has huge global saturation on a consumer level, but most business is done primarily in their home offices. They are able to stick primarily with their 1st party games and have found their niche there.
These are 3 VERY different companies and I'd say they have very different customers, even more-so with what it seems like Microsoft is trying to accomplish. The only reason I'd think of buying an Xbox is to play a new Elder Scrolls or Fallout game, but, honestly, I just started playing Fallout 4 and it's not even close to as good at Fallout 3 or New Vegas, so I'd probably be happy with sticking with Playstation.
This acquisition is showing Microsoft's hand a little bit, it's a bit of a big bluff. Looks like a power play on paper, but they mostly bought several dying IPs, I guess hoping that the player base will return to games like COD as if it were the early 2010s.