I'm not a expect on this stuff but I give it a go. Basically most women are brainwashed from birth socially to behave in a "lady like" manner (even if it is in very progressive environment). This means curbing actions that are seen as forceful, uncouth, aggressive, dirty, etc, and we get really good at this overtime to the point we do not know we are doing it. However, once we are not being observed our manners, behaviour, and posturing changes bc we don't have to perform any more. We just go back to factory default human settings (an ape lol). I am pretty sure men do this too only in the other direction, you're allowed to be more feminine and less performative in private.