Because men — and particularly white men – have dominated history and history classes for far too long. It’s time everyone starts to learn about the multiple sides of the same story. Everyone has different interpretations and everyone will leave certain details out to make themselves look better/smarter/stronger/etc.
Besides, why do you think people say “behind a good man is a great woman”? Women have always made the world a better place, although we never get the damn credit for it. (Men can be so rude sometimes.)
Anyway, go read this article. It’s really worth it. And hopefully you’ll try to find multiple sides to the same story, one story at a time. That really does open up your mind for the better.