It’s still demeaning (by our standards) because it’s defining a woman by her relationship to a man rather than as herself.
If it was truly innocuous there would be a male equivalent, where he would be referred to as Mr [HerFirstName] [HerSurname] but there isn’t. Why? Because the men are more important than the women. Men were never defined by their relationship to a woman.
Which is another reason to completely abolish that outmoded practice.