My implicit point was this: Nesov2006 probably did not realize that Nesov2006 was a fool and Nesov2008 probably did not judge himself to be a crackpot.

To a significant extent, both would agree with my judgment. The problem was not so much inability to see the presence of a problem, they just didn't know its nature in enough detail to figure out how to get better. So the situation is not symmetric in the way you thought.

See The Modesty Argument for a discussion of why I won't believe myself crazy just because there are all those crazy people around who don't believe themselves crazy.