Eric, I hope you'll forgive an injection of some humor:
http://www.smbc-comics.com/?id=3474#comicWhat I mean to bring from Mr. Wiener is this: as you say, you've had a successful career or two, you're a parent, and in general have got a lot going on in your life - enough so that getting declined is, as you say, “barely a blip.”
Your perspective is very likely vastly different than most judges. In my (anecdotal) experience, judging takes up an awful lot of emotional energy; a lot of people put their heart and souls into this, and thus being declined from an event hits far harder.
This isn't about trophies - after all, no one is advocating application acceptance for all. This is about good sportsmanship and not being an overly exuberant winner.
Obviously recommendations for Exemplar are subjective, but I can certainly speak for myself in that I would take public behavior into account under Attitude and Maturity. More importantly, one of the main objectives of the Exemplar program is to ameliorate the impact of being declined for a Grand Prix. Instead of foils only going out to a very limited set of experienced judges, the pool of eligible candidates will be essentially unbounded. Even though you're likely correct in that this issue will recur somewhat with Exemplar, the hope is that a greater emphasis on merit will make these rewards more fair and achievable to all.