Because that's how the majority of the world has been for thousands and thousands of years because we lacked technology and had societies.
Even 300 years ago it was that way in most of the world. Trying to say the bible is that way specifically is ignoring most of our own history as well.
In a world where every day is a tough and grueling day where constant physical stress and work were required to live, no electricity, no cars, no indoor toilets or anything life was not easy for almost everyone.
So men being the stronger, tougher, more aggressive, more able bodied to work, fight and hunt were the ones to lead and women were the mothers, the caretakers, the helpers.
And back then that was the symbiotic relationship needed to propagate the species. It's a normal and natural state of being that still exists in the animal kingdom for the most part now.
Modern society in a civilized society has changed because of our advances in technology that makes our lives much easier, that's why you see little of that dynamic right now in say america.
Just tossing off a closed ended comment with little to no thought isn't proper thinking. To grow you need to look at reality, the past, others points of view and think outside the box instead of being a slave to impulse reactions.
