Back in the stone age, men went out and hunted for the food, while the women tended to the children and cooked the food for everybody.
It is definitely not considered unmanly for men to cook. Just check out all of those dudes working the barbecue grills.
Probably in your average family, the cooking skills (and chores) have simply been handed down from Grandma, to Mom to the female children and at least up until the mid 60’s cooking was considered to be an essenstial task of women, who were usually homemakers, who didn’t work outside of the home and raised kids and did all of the housework. Some of those ideas are still held, not necessarily because people believe that only women can or should do those jobs, it’s just that they are taught those jobs that have been handed down by their own mothers and grandmothers. The boys are not always expected to learn how to cook, but the ones that show an interest are usually welcomed in the kitchen. Those boys grow up to become chefs.
Most of my male cousins, although none of them are professional chefs, are fabulous cooks, and so are all of the females.