The point I made is this: the word man is not static in the sense of only referring to biological males, but can refer to mankind, specific professions or stations (the members of which are not necessarily male) such as postman, lineman, or policeman, or to an individual member (not necessarily male) of a group or team. Man does not always specifically mean biological male, nor does it always refer to a biological male. It isn't all about sex, and there is so much more to life than sex. or biology, for that matter.
Other relational words are not always confined to biology, either. Father, mother, daughter, son, brother, sister does not always refer to biological father, mother, son, daughter, brother, or sister. Aunt and uncle can refer to a wide range of people, not necessarily family (biological or adopted) members. Cousins can be stretched even further, sometimes even referring to relationships between two different species. Man has an even farther range than that.