All three of the big three need more studios, because they're all suffering in games right now. Microsoft's solution has been to buy a third party exclusive from a third party developer, which gets them nice support, but doesn't really impress anyone. Nintendo's solution has been to stick to their guns and keep pumping out what little they can, which has resulted in a good number of really high quality games, but hasn't really impressed either. Sony's solution has been to get a bunch of smaller teams to make a bunch of tiny indie games and show off big numbers like "40 new PS exclusives coming this year!", which has resulted in a lot of good smaller titles being made and pleasing the indie crowd, but overall also fails to impress. More studios working on more big games could help, but the issue with that is, well, more studios are incredibly expensive. Even Microsoft isn't founding a lot of new studios or even buying them, and they invested a billion dollars in games this gen already. There's really no easy solution to this.