Why is this the case in at least some cases?
Surely most of them have grown up with women in their families (mothers, say, and even sisters), so they should be aware that the vast majority of women don't squeal and skip and grin manically all day long or that they don't go out into nature in high heels and wearing leather bikinis or that they don't panic when seeing a bug and then trip over and end up lying exhausted in the grass?
And where does the fairly common idea come from that living as a woman means being pornified in dress and behaviour all day long?
Probably from porn? But then, once again, how about observing women in the real world, to fix that misunderstanding.
Also, why doesn't identifying as a woman more often mean to identify with getting the groceries, cooking the meals, cleaning the house, wiping the noses and the bottoms etc? The actual boring stereotypes which are attached to the female sex.