[muir_redwoods]

Evolution doesn't make us taller, survival advantage makes us taller or shorter or wherever the advantage lies. Good nutrition will allow us to come up to our genetic height but we will, as a people tend toward the greatest advantage for survival in all of our traits unless we artificially interfere

[Frumious Bandersnatch]

I agree with you that it is not an evolutionary trait. But you might note that since it is a survival advantage, it does loosely fit the definition of "natural selection" - a prime argument used in evolutionary theses.