I mean, it makes sense why most husbands would not see their wives as equals. This is a patriarchal society after all. Women were only raised to do things like embroidering, obeying a man, etc. It's only recently in this current generation that multiple women are starting to show their talents. The duchess's growing fame, the princess taking charge, and even that one redhead noble that looked down on the duchess at first.
A single woman being the exception isn't enough to change opinion. More and more women have to take charge and inspire others to follow suit.