So a XY person with androgen insensitivity syndrome is a man, even though they completely lack all male features (except a pair of testes hidden inside the lowe

So a XY person with androgen insensitivity syndrome is a man, even though they completely lack all male features (except a pair of testes hidden inside the lower abdomen) and have breasts and, in some cases, a uterus? And such a person can live their entire life as an (infertile) woman, never knowing about their genetic abnormality, they are a man? And then we have X, XXX, XXY, XYY, XXXX, and XXYY people walking around, living and breathing, some of them fertile and presenting no recognizable signs. It's crazy to me that someone would use knowledge of genetics to argue that there are only two "biological" sexes and nothing else exists. Biology is messy and full of edge cases that defy easy and clear definitions. To take a convenient rule of thumb (XX <=> female, XY <=> male) and declare it a universal rule is either ignorance or motivated reasoning.