I don't really know why people think Nintendo couldn't build a successful machine with full third-party support.
They undoubtedly could.
Even Microsoft did it and they worked from scratch. Even after a major issue with the 360, they did very well with only a handful of exclusive IP.
The issues isn't that Nintendo couldn't do it, the issue is that Nintendo doesn't want to do it. It would take a lot of work and money to reach what Sony and Microsoft have done in terms of building up their infrastructures and establishing business partnerships. After years of falling behind in those areas--or ignoring them completely--they'd have to commit major resources just to draw even. Nintendo doesn't really like investing in things like that until they have no choice.
It's simply their corporate identity and has been from the start.
I think of it like baseball. Sony is out there hitting singles and doubles, playing defense, stealing bases--they work hard on every facet of the game and win with teamwork. Microsoft is the team that signs a few big name free agents but fills out the rest of the team with role players. Nintendo, though, goes for the home-runs. Defense and teamwork? No, they want to hit the ball out of the park. They want A-Rod instead of Jeter. When they do, they win big. When they don't? Strikeouts.
Nothing wrong with this, of course. It's their philosophy. They can do what they want with their own business and I'm fine with it. Speaking as a former Nintendo fan, I'm more than happy after switching to the competition, so I see no need for Nintendo to join them. Of course, I can understand the frustration of someone who wants Nintendo games and third-party titles but that simply doesn't seem to be Nintendo's path.
But could they do it? Yeah, if they made the effort. Maybe one day, when the company is no longer run by old men, they might try.
