You're comparing the price people can afford to the price people are actually paying. For example, practically everyone can afford the median price of a pack of gum, but few car buyers can afford the median price of a Jaguar.

Also worth pointing out: the median-price is the price among all homebuyers. It's not necessarily true that half of a subset of those homebuyers can afford the median. For example, 100% of the highest-income homebuyers can afford the median-priced home, but roughly 0% of the lowest-income homebuyers can afford a median-priced home.