I think it's actually because we've got our values completely mangled regarding the good, and we've got a sort of populist idea. George Walden wrote something very interesting about this a while back in a book called The New Elites:
"Royal persons may not appear to serve much in the way of a practical purpose, yet the media have found a use for them, and popular they most certainly are. The public know what they like, they like royalty, and were infatuated with Princess Diana... What the public appear to be telling us about the monarchy is on any enlightened view retrograde, sexist and undemocratic: that you are a superior person if you are born into the Royal Family, and especially superior if you are a young woman who chances to be good-looking and who marries into it. Should you be a commoner and a male of indifferent looks and, by dint of talent and application, make yourself an expert on classical Greek literature, then you are suspected of elitism and placed, mentally, under armed guard. The conclusion would seem to be clear. In our populist democracy it is all right to be royal, sexy and not over-bright, not all right to be plain, a commoner and smart. Which makes nonsense of democracy. But there you are: the people, being sovereign, must be allowed their little quirks and contradictions." (p. 10)
As Walden points out, we aren't completely against people being better at something than others. For instance, if we are to have surgery, we quite clearly want to best qualified doctors to perform the operation. We want the best footballers to represent the nation in the World Cup. But we aren't quite so worried about having the best poets or the best artists or the best musicians or the best classical humanists.