I don't know about you, but I don't give a damn about made up problems that aren't part of my life. Don't get me wrong, I can totally imagine smug vegans. I just made the observation that 99 percent of the ones I met would receive a disservice if I went under the assumption that "all vegans are smug assholes".
Similarily my assumption for meat eaters isn't that all of them are assholes. But I observed there are people who are so triggered by the mere thought of vegans existing, they can't stop talking about it or demanding from any supposed vegan that they explajn themselves — so the exact thing they claim vegans do.