Pardon me for being harsh and unmacho.

The cultural attitudes being defined as masculine here, which I usually call being macho are the attitudes of teenage boys. That pushy, trying to assert power, playing king of the hill sort of thing. The 'alpha male' idea. That's biologically unsound among other things since our species doesn't have a biggest horns means being the only one who gets to mate.

In any case. At the core of this attitude is a combination of fear, pride, and an unwillingness to see women as human beings worthy of individual respect.

What some call losing masculinity, I call growing up.