Really M and F are losing their utility.
Does a t-shirt, or dress, or thong, care that the woman on the left is XY? Or the man on the right is XX?
I think it would be easier to have an international universal unisex sizing chart, and let people buy whatever they want. Freddy Mercury wanting to buy a pair of velvet pants in Bohemian Rhapsody, and Mary the salesgirl telling him “This is the women’s Section.”
I’d like to be able to walk into a store in any part of the world and say, “What do you have in a 44?” Which today may also be a 46, 49, or 54, depending on where you are. “Do you have this dress in a 44?” Why not?