Yes, it turns out if you want to use the mechanisms of the legal system to try to counter the marginalization of any group by the whole system, it has to recognize them in law and provide a method for distinguishing them in practice.

But, once you have some method of distinguishing them, the people that want to strengthen hierarchical structures will use that to identify them and (further) marginalize them.

This is true whether you are talking about chromosomal properties, internal anatomy, external anatomy (not limited to genital shape, but also melanin quantity and distribution), gender-assigned-at-birth, current gendered behavior, religious practices or associations, etc.

Still legal recognition might be the best way to reduce harm until we can achieve a future where the category or distinguishing characteristics no longer make one a target of (extra-judicial) marginalization.