There are lots of unearned advantages in sport, sure. But there are also impermissible advantages. As Bill Burr put it, we make fake legs so good now that it's better to have no legs if you're an Olympic runner (well, it was). Doping gives an advantage, but it's notionally banned. The distinction, as one paper I read put it, is between tolerable and intolerable unfairness. Sports does not celebrate competitive advantage, but competition--the problem with intolerable unfairness is that it ruins the competition by creating advantages that crater the sense that there's a real chance of a game, or if it creates harmful incentives. If China created an army of genetically engineered athletes that performed 10% better than everyone else, the Olympics would be even more boring than they already are.