In the past, fitness (and hence its proxy parameters like height and other beauty standards) correlated to the survivability of your bloodline. So it makes sense that people are programmed, to a certain degree, to admire things like tallness.

Nowadays because of technology the correlation no longer exists, or at the very least it is much diminished. But the programming is still there right in our DNA, so as a people we should artificially override this natural instinct because it no longer serves a purpose.