D&D doesn't need elitism, as long as the players have their character sheets, dice and are contributing, that should be good enough. In short, I still find the OP's claim to be ridiculous and please don't compare D&D to a sport.
Why can't I compare D&D to a sport?
I like to run. I like to ride my bike. I'm not particularly good at either. It doesn't stop me enjoying what I do that there are elite and competitive runners and cyclists out there. If I wanted to join their teams, it would be on me to step up to their game - they're not obliged to take me just because I'm eager.
I also like to play guitar. I'm not particularly good at that either - I just play songs at home for fun, or for my kids. If I wanted to join a band, it would be on me to practice and improve.
If some people want to play "serious" D&D, that's their prerogative. I've played with D&D groups who, by my standards, didn't take the game seriously enough for my tastes. I wouldn't want those people as a permanent part of my group.
The well-knowm report from the Origins tournament where Tomb of Horrors was played (Alarums & Excursions #4 September 1975) includes this:
As characters were assigned in alphabetical order I ended up as a 6th rate Magic user- supposedly the weakest in the group. Four of the fifteen had any previous experience. I grabbed the callers spot and announced the imposition of military discipline. Judging by the way the game went, Slobbovian army. . . .
[T]here were no wandering monsters (damn few monsters at all, in fact), plenty of traps (too many) and very few experienced players. It was run by Gary's son, who devoted no effort to keeping the characters in character. However, we did just as well as the other Friday night group- with 13 expert adventurers, that many would be callers- and perhaps just a shade to much caution. . . .
Paul Bean having chosen our spells while I described D&D to the 11 novices and Gary's son wrote out the character descriptions . . . No names were assigned to the characters. The remaining two experienced players- New Yorkers I think, retired into a corner to determine their own equipment. It quickly bacame obvious that they had tabbed me as the bossy type and didn't want to argue. The situation- which was dire- demanded such behavior, however. A little more assistance would have been usefull. Paul and I made a bad mistake at once- not being used to playing with single use spells we did not take enough multiple copies of the more usefull ones. . . .
#2 and #3 fighters fell into a trap . . . We dragged them out. Should our Patriarch raise them from the dead? After 5 hours in the Barren Lands my condition might have been described as numb. With a hazy idea of saving the spell for later I ordered them dropped back into the pit for later recovery. Neither the Paladin nor the Patriarch protested. The Dungeonmaster did not tell them they should have (both were neos.) No one suggested that we take their useful equipment along with us (one had a bag of holding.) At this point I ordered a Locate Traps spell used- a bit late- and we avoided two more pits on the way down to the end of the corridor . . .
That's pretty close to D&D-as-sport. You mightn't want to play that way. I certainly don't want to play that way! But it's a pretty time-honoure way of approaching the game.
People of any strokes who think others who don't play/think/feel/game like them are therefore "playing wrong" are an unfortunate burden on gaming everywhere.
Agreed. Including those who think that playing "serious"/competitive/"our goal is to beat the dungeon" D&D are doing it wrong. That's an approach to D&D play that's been around for just about as long as the game itself. Gygax called it "skilled play", and outlined the basics of the approach in the final section of his PHB for the AD&D game.