I always wondered why the government even needs to know our sex/gender? Even just biological sex is almost imposible to define in a way that includes everyone as soon as there are millions of people (e.g. ambiguous genitalia, chromosome variations like XXY (either looking more male or more female), XX-male, XY-female, PAIS, etc, etc).
I'm here in the Netherlands? By law everyone is treated the same by law, regardless of sex? This government doesn't even need to know your sex when you are getting married! It's just not relevant. So why do they insist on recording it?
At best, it's only use seems to be to know how to start a letter with either "Geachte heer" [male] or "Geachte mevrouw" [female]. Nothing else.