Ultimately it gets down to the fact that the differences are due to socialization and reinforcement of gender norms throughout ones life. The point is we're not born that way. We're born across that spectrum.
Therefore, we'd be better off accepting.peoolr as they are and letting them develop as they would without the gender boxes forced on us all from the moment we're born.
It would also allow natural shifts during life that would benefit us and our families as circumstances may dictate. For example, Grandpa can tap into his nurturing ability to keep the frandkids after retirement rather than forcing Grandma to take early retirement or Mom to quit a lucrstive job that benefits the whole family.
The problem with gender boxes, well ...one of the problems with gender boxes is how they cause misery and immiseration by preventing us from adapting to our circumstances.