It has been quite common in my career to routinely write professional, formal letters to a wide variety of people, some who I know well and some who I don’t know at all past the limited business at hand. When I first started, the variety of prefixes for women was still technically the correct proper form and, simply as a practical matter, the large majority of recipients were still male. Not knowing the marital status of a female recipient required a generic feminine honorific as, at least in the context I was generally within, marital status was entirely irrelevant. It seemed a bit silly that it was common when sending a letter to a female, regardless how accomplished or lofty her position, a prerequisite was to review any prior correspondence from them to see if they had provided the clue of referring to themselves as Mrs., Miss, or Ms. Some would get quite offended if not addressed with their preferred prefix. There was a subset who would also get offended if referred to as Ms. or even Mrs. Jane Smith; they had to be referred to as Mrs. John Smith. My mother was one of them, I never understood it, and she couldn’t ever explain it to where it made a lick of sense to me. It seemed the “Mrs. John Smith” stuff went out with addressing minors as “Master” and “Mistress”.
Personally I was glad to see a general societal trend toward acceptance of a generic “Ms.” and “Mr.” in formal correspondence. It feels a bit too personal to have a constant reminder of a professional contact’s marital status throughout a business deal, particularly when the roles are adversarial.
I do still have occasional issues with gender neutral names of people of whom I have little personal knowledge. Is Pat McCrory a Mr. or Ms.? How about Pat Benatar? (I can get those two but I’ve never written a letter to either so not useful knowledge.) For those I still sometimes have to use the full name without gender specific prefixes.
