Why, after all these years of evolution, does being a hard-a$$ and having machismo mean so much?

I see it everywhere. On the job, on the street, in traffic. I hear the tires squealing, the motors gunning, the shouts and the threats... I see the gang signs, the puffed-out chests, the muscles rippling, the dirty looks, the bar-fights started cauz somebody looked at someone funny.... the testosterone may flow, but you don't have to be a caveman, dragging women back to your cave... I know a real man who is gentle and warm, doesn't take crap but doesn't start crap either, takes care of his kids, is a pillar of strength to deal with all their problems, and still has time to be my friend... a rock with a big heart. He is evolved. So why all the crap? What are you trying to prove? Anything that means anything in the end, other than you wasted your life trying to be a man while others simply are?