I think what's being ground up against here is that weapon proficiencies tied to race inherently don't make sense in most cases, so arguing lore justifications are going to work.
Polarms for humans is as legitimate as swords and bows for Elves, yeah you arnt innately born knowing how to use one, but the cultural importance placed on them means you probably know how to use them if you are of said race.
Learning how to use a sword and a bow as part of "becoming adult", along with proper manners, the 27 most important dances, the 341 most noble poems, and the proper way of strutting about in the meadows, does arguably make some sense for a species that lives for hundreds of years and don't have tiktok to mushify the brains of their youth.
But all humans taking the time to learn how to polearm is a rather different story.
