You illustrate this perfectly!
"I knew very few people (in a heavily "red" state) that would fess up to wanting Trump. Based on that observation, I suspected they were probably too ashamed to admit that to an anonymous pollster and possibly to themselves."
Too ashamed to admit to themselves? You arrogantly assume that anyone voting for Trump SHOULD be ashamed! This smug demonizing of people with views you don't like is exactly why the Trump voters kept quiet. The Left in America seem to feel they can spout anything they like, and demean anyone they like with impunity. Those who disagree with them are obviously stupid redneck Nazis and their opinion doesn't count. Which is utter bigotry, but only white males can be bigots yanno. Bah.
This tactic has left many Americans rightly annoyed at being insulted and marginalized. In my opinion, Hillary voters have at least as much reason to feel ashamed. In truth, neither were acceptable candidates, which points up the failure of the Big Two parties.