Its when mothers themselves teach their daughters from middle school to look for taller guys "to feel protected" and also teach them things like "shorter guys make good friends" which is what makes it mainstream and acceptable.
It may be biological, but even then it we would take the social aspect of it, we may have a society where taller is better for a male, but if you're short its alright just like many aspects. It would end up being an actual preference. Not a dealbreaker.
ここには何もないようです