Tenure vs nontenure jobs
Justin, I think you raise good questions, and I'll try my best to clarify what I intended to say.

Regarding the first quote you cite, I did not meant to imply that in general non-tenured faculty are dysfunctional. The vast majority are incredibly dedicated and hardworking teachers. When I said "most", I really meant that most adjuncts who believe they have proved a major theorem (as Zhang did) are almost always wrong and usually "have very dysfunctional personalities and lives, and are unpleasant to deal with, because they feel disrespected".

As for the second quote, I was trying to be facetious. Those of us who are tenured professors know how many responsibilities and duties we have in addition to our research and teaching. So I like to say that Zhang had set up the perfect situation for doing research over a long period of time. He didn't have tenure (which as I said entails a lot of distractions) and just had to teach calculus (which, after a year or two, requires minimal preparation time outside of class). In addition, he had no children, and his wife lives on the other side of the country. This was perhaps not a good joke for a broader audience, but my colleagues all get it.

Finally, my point about Zhang is that he really was a good mathematician who had received very little respect from his peers and yet showed no signs of being bitter about his experience, even though he certainly would be justified in feeling that way.