They were a mutation in the genes, and function as the disposable breeding class. Their y chromosome is held together with silly string, and their pleasure organ is also their breeding organ (meanwhile women have a clit separate from the vagina and womb). For 2/3 of history life on earth was female only, and nowadays plenty of female animals who have males in their species can parthogenically reproduce. There was even a mammal that did it, the mouse kaguya. I'm sure back in tribal times men were useful for fodder against animals and for scouting new land, since the tribe won't suffer if they lose a few. They were sent to hunt just to get them out of the women's and children's hair, and to tire them out. Their hunting only supplied up to 20% of food for the tribe, while women's foraging supplied the vast majority.

They say it themselves, they feel purposeless. Most are content to exist in capitalism if they get a fuckhole and ego boosting at home. Or more commonly nowadays, they just parasite off their mothers forever. These creatures are clearly on life support by now, and you don't even need to look into their dna to see it. I'd say it's time to end this experiment, stop making more of these disabled creatures. We can make sperm out of anything in the lab these days, balls in a bottle!