Well, I'm not going to act like some people don't interpret their success as a mandate of how exceptional they are overall, and I'm sure being somewhat more intelligent than average in an industry known for sycophants probably leads to some unhealthy mental self image problems. These people definitely seem to exist. I think we should be careful to not let our admiration and displeasure of each set color our interpretations of the other though, and keep in mind some people are just trying to help where they can.

the popular understanding of the Dunning-Kruger effect

You had me (my upvote) at hello (the acknowledgement of the popular misunderstanding). ;)