This is going a step further than what I always thought as being unnecessary: having your sex on ID and passport.

I don't see any real reason why this is still required, or why it matter that the sex of a person be present on an ID document. The purpose of the ID is to identify the bearer. Most ID are now biometric, meaning the identification relies on unchanged physical features, like geometric relationships of the face.

A simple photo should be enough to confirm the ID of the bearer.