> Voluntary military service was also male only, so I'm not sure why you are focusing so much on conscription.
Most worlds armies are conscription, and even the US army had conscription during the American Revolution, the American Civil War, World War I, World War II, the Korean War and the Vietnam War. It culturally defines the military.
> This perfectly illustrates my point.
No it does not. Men as a group did not keep women out of conscription so men alone could get the privilege of being conscripted. It not a privilege. A better claim is that society pick which ever demographic is most expendable and force them to pick up arms during major conflicts. Young men, especially men of color, is consistently seen as expendable. It is racism, sexism, ageism, and a bunch more isms, and part of it favor women over young men.
During world war 2 almost all nations involved used prison population for conscription purposes. It is the most obvious place to find a lot of expendable people.
Voluntary military service still carries with it that culture and non-expendable people tend to not be near the front line.