"...the primary purpose of "nature" is to facilitate procreation of every species."

Nature doesn't have a 'purpose' in the sense we mean it. Evolution DOES work in such a way that procreation is usually assured. That is sort of automatic, or we wouldn't be here, but 'nature' produces many variations on the theme which don't affect the procreation aspect. Perhaps there's some 'purpose' in that also.

I DO know that when I was still in my teens, and saw some of those good-looking gay guys, I was quietly relieved that they were not competing with ME for girl friends.