he might mean that mothers might have a natural advantage over dads through microchimerism when it comes to child bearing, and mothers are also favored by law, so it's not what they
bring to the table, it's what they are given by nature and law
as far as i'm concerned, it was my mother who raised me while my father was either working or drunk. my first memories of my father being a father come from my early teens, not from my childhood. my gf is a cool, fun and dedicated mother, so my son is fucking lucky to have her, regardless of nature or law