If East Asians Developed Epicanthic Folds To Adapt To Snow Blindness, Then Why Didn’t Northern Europeans Develop The Same Trait?

Question

I’ve read that East Asians developed slanted eyes or Epicanthic Folds as a way to adapt to snow blindness in the more snowy and colder regions of Asia, and I was wondering why Northern Europeans, specifically Germanic and Nordic people that lived in the colder regions of Northern Europe, didn’t develop the same genetic trait or at least something similar to it.

In: 973

Answer 1

I heard is also helps with dust storms.

I’d argue 4 Months snow blind + 8 months Not snow blind is conducive to non epicanthic folds.

But 4 Months winter + ongoing summer dust storms is very conducive.