Since we're on the topic of unpopular-but-true, I'll go ahead and post another: It's not about whether we can program so much as what we can accomplish by learning to program while we're young. You and I may make fine and capable employees, but some want more than that. It takes more than just ambition: it takes positioning and luck. I hope it won't be too controversial to say that younger people can take more risks due to the fact that they're young. Therefore they will take advantage of the lion's share of the luck.
In other words, if we were willing to sacrifice our dependents to take more shots at the type of success which attracts people to YC, then we'd be in the same position as someone who was young. But we aren't willing, so we're not in that position.