Cause biology and mother nature have different plans.
- Survival of the fittest -
Which usually means strong physique -> Short people do not desplay that.
And that quote transfers into the modern society as less status.
Its all about the programming of our mind -> reproduce -> makes men competitive towards other men -> makes women look for the "strongest" man with the heighest status.
Short men also tends to get damaged over time by the hatred, that causes us to be different and valuable which is also considered a weak factor.