The human side of me feels a bit bad for this guy. Hope he lands on his feet soon.
However, the more rational/logical side of me thinks this guy has made a string of bad decisions throughout his life, culminating with this ill-advised podcast appearance. He should really surround himself by good people and follow their life advice.
I'm not speaking as a video game fan, but as someone who's been working for a long time now. Nintendo is within their right to terminate him; as others have said, that's almost the "light" punishment since I'm sure they can find cause to go after him in court. NDAs are in place for good reasons, and violating the terms of Non Disclosures are really a black and white matter. At least many companies treat it as such, and many provide mandatory (usually yearly, if not more often) employee training on safeguarding information and the consequences of not following those rules.
Lastly, I am kind of baffled at his apparently EXTREME emotional attachment to a for-profit company. Building your whole life identity around a company is at best a fool's errand, and at worst... yikes, I don't even know.
I hope he learns from this experience. Good luck to him in his future endeavors.