They rarely ask men.
No, they ask men all the time. I was asked 100s of times. They may think a petite young women may not care as much. My daughters like the window seat. And big men have a hard time getting into a middle or window seat. So, men, especially big or tall men are less likely to yield a isle seat because its too obvious. But that does not stop them from asking us and appealing to our chivalry gene. If I did have a window seat I would move, because the middle verses window does not matter much to me.