When I was growing up, it was taboo to say the word sex, because it also refers to a "rude" act. People would say "gender" when they meant "sex". The idea that sex (the classification, not the act) and gender referred to different concepts was not commonly held by the general population - those whose vote implies some kind of collective consent to the laws that get passed - so wherever "gender" exists in the law, this is the way in which it should be interpreted, at least by default.