Many of the posters on FWR freely admit that they enjoy dressing as women - heels, make up etc etc.
Firstly: This type of visual display is only 'dressing as women' in our particular time & culture. There have been long periods in our own culture when men wore higher heels, frillier clothes and bigger hair than women.
You are confusing sex/gender with fashion!
Secondly: High heels, makeup, etc, etc, are sexual displays. In our current culture we like women to wiggle when they walk, have enormous eyes and prominent breasts, and so on because these are currently considered signs of sexual availability.
I'm not saying there's anything wrong with signalling sexual availability. In a genderless society, we will still make it clear we're sexually available when we want to.
The differences are: We'll choose when & how to signal it. We won't feel that one sex has to go around constantly advertising, while the other doesn't.
Female brain, male brain
There isn't even a smidgeon of evidence that male & female brains are inherently different. The differences which have been observed, like a bigger 'map area', have also been observed to correct when women get the same training as men (this was tested with black cab drivers doing The Knowledge.)
With current science it's impossible to evaluate whether male/female brains are different at birth, because a newborn's brain is pretty much neural soup. The soup forms into a recognisable brain in response to the experiences of the baby.
That's an oversimplification - but hopefully a brain scientist will pop in to confirm my basic point, which is that the 'conscious' parts of the brain gain their shapes after birth, meaning the world around a baby forms its brain. This is why gendered treatment of babies is a concern: when you treat a child 'like a girl', you make it develop 'lady brain'.
Here are some fashion pictures from our own history :)