Chivalry and basic middos do not have to be equated. SOME things from the chivalric times are part of basic human decency that still should be kept even though chivalry in its basic form can contradict halacha. Men need middos classes if they say that any chivalric actions are contradictory to halacha. I understand that men should not walk behind women,but does that mean that the woman should walk in the street to be able to let the man pass them on the sidewalk? (This story is true. The man stomped his foot at the lady walking so he could pass her. the only place for her to go is the street. Why didnt he just walk on the street and pass them? They obviously did not know he was there.) Why should anyone be treated by garbage just to be able to be “extra machmir” not to follow the practice of chivalry? Opening the door for an elderly lady, or a mother with her hands full of packages or groceries, should not be an issue, especially if he walks in, and leaves open the door for her. He still is ahead of the woman. Or he can open the door, let her walk in, wait a moment and enter and pass her. There is a difference between “unbecoming” and halacha. Follow halacha but remember that you should not be machmir at another’s expense.
Just a note: I am not a woman’s lib follower, I think that their ideas are full of problems.