Because women have uterus, and we bring life. Some dude DEFINITELY NOT THE "ALPHA" of the tribe, had to invent a wholelass religion because he couldn't handle the fact women can choose partners and choose who they give their offspring to, and other dudes followed him because they saw they can entrap women into low self confidence with religion, societal brainwashing, rules and everyone, now even the one male specimens that shouldn't mate and procreate because of lousy genes can have children they don't deserve and a wife and regular sex. They added more slave labor onto the first one and so patriarchy probably formed.
