OP has made a strong argument, one that I read over and over, just take make sure I wasn't misinterpreting. I really only want to add one little note:

"Elitism" as it is used in our gaming world, isn't truly defined by the actual textbook definition. It has taken on a different, more extreme form in our community. Here, I see "elitism" as not just being superior to others, but taking every opportunity to remind everyone else how superior you are. Whether it's bragging, or putting down others who don't meet your expectations, the attitude of superiority is what "elitism" has become known for.

What the OP describes is more akin to a "veteran", I think. As one poster mentioned before, many veterans can become fatigued with other players lack of skill. Heck, I'm one of them. But a veteran doesn't feel the need to gloat to or berate others.

TL: DR - You can be good at a game and not have to brag or criticize everyone else. When you do, you become the new definition of "elitist."