Unlike some species, humans have pretty mild sexual dimorphism: men and women are only a little different, beyond the obvious (but hidden) bits. Not like the sage grouse, for example.
But we do what we can. For example, I always thought the bathroom icons were the same except for the dress they put on the woman.
But on closer inspection, their bodies are a little different, too.
She has skinnier legs, and his shoulders and torso are broader. Plus, her arms are angled out, as if she has wider hips under that dress.
Are the different bodies necessary? I think if they just put the dress on the man’s body, and angled his arms out, he could pass as a woman.
Or, if you prefer, take the dress off her, and let her arms hang freely:
In other words, I think it’s all in the dress and the posture. The different body types are gratuitous. They do contribute to the total effect — but only if the figures are shown side by side and with different clothes. In isolation either body would do as long as the clothes were different. That means the clothes and posture are teaching us about the body types, not vice versa.
The man is the generic “person,” and the woman is a variation. That view of sex differences goes back to (the story of) Adam and Eve, and was also the dominant Western medical model till the 18th Century or so. If fact, everyone starts out as a female fetus, before some people are made male.*
(Of course, this kind of subtlety is only necessary since we’re not willing to use exaggerated body-type differences as symbols – that’s a different website.)
If just putting the man in the dress doesn’t do it for you, how’s this?
* In recent days we were reminded that there are “suicide bombers” and then there are “female suicide bombers.”