If Martha Washington had been in charge of Mount Vernon instead of George, the U.S. and Canada would be a massive British colony right now.
Actually Martha DID run Mt. Vernon while George was at war. He only visited once during that whole time, on his way to Yorktown.
Yes, he appointed a brother to oversee but he did not live there constantly running things.
Never mind the many examples of women in positions of power. Often recognized as the greatest of rulers.