Why are you talking about social gender as if that expression in itself is something completely separate from what made it appear in the first place?

A social construct isn’t infinite in its expressions since the social construct is emanated from a structure that is biological. There are universally known typical characteristics of both sexes in terms of social behavior and there are links between extremes of a certain cognitive aptitude and physical appearance.

There are great overlaps and the differences aren’t always huge. In fact, sociological perspectives can give us great value but you are making it seem as if gender expression has no ties at all to biology which is a ludicrous general claim.