I have to disagree here.

Gender roles and gender expression are social constructs. Even gender stereotypes are a social construct, but gender itself is not. In legal contexts, sex and gender are interchangeable.

In the trans context, gender refers to gender identity, and is a neurological trait.

I also disagree with your statement regarding race: racial consequence is a social construct most definitely, but where does that derive from? It is a societal desire to treat people of different races differently. Race by definition certainly exists, and racial identity (as a lived reality of the consequences of one's race) also exists, and is very much biologically real.