Yes, that is an Achilles Heel, of sorts. But like the actual injury, it's not fatal. Competition is inherently exclusionary, but that doesn't mean that nothing good can come from it. It just means that we should keep it in its proper perspective. Competition is good in that it can push you to be the best version of yourself, and there's something about sports that has a certain level of purity to it. Unlike politics, in which a candidate can rationalize a thousand different reasons outside of their control about how/why they lost, in sports it's a lot more simple. You lose when you don't play as well. If you don't score more points than your opponent (or less, if it's golf) then you lose. You might disagree about strategy or tactics, but the basic outline is pretty self-explanatory. If the other team beat you, they played better. It might be because they were more talented or it might be because they maintained greater focus or because they had a superior game plan, but they still played better. So if you want to win, you have to find a way to play better.

Very few situations in life offer such a clear, unambiguous path toward self improvement, and I think it's one of the reasons why sports are popular because they're easy to understand but difficult to master.