There's still room for ambiguity or disagreement, though. Just from the top-level: Does "biological sex" refer to chromosomal sex or to anatomical sex? By either definition most (all?) individuals will be closer to the norm for one or the other. But in a handful of cases, including the one that you linked to, an individual will be male by one definition and female by the other. I don't see a particular reason to favor one definition over the other when talking about biological sex.