[zillolo]

Male and female are clearly defined (not really, but let's assume for the arguments sake). Intersex people exist, and they are impossible to identify without them telling you about it. So these people are really "assigned" a gender at birth. They might not be a huge amount of the population, but they exist. So why not use "assigned at birth"? It includes them and doesn't hurt anyone at all. I'd ask you to reconsider, whether the authors made a political statement, or whether you made this a political statement by yourself. Because I read it and not a single political thought crossed my mind...