when did we stop addressing everyone as "Mr" & "Mrs"?

When society starting adding more genders.

Because it is sexist. Get with the times. More than 2 genders, and having Mr in Mrs is slavery.

Plus won...It is not that hard to show respect and common courtesy, respect, and manners.

My grandfather has been dead for almost 5 years now.
If I catch myself not saying it, I duck my head ....habit. I can still feel the wind of his upcoming slap.

I address older people as Mr or Mrs... No matter what. There are times when I strategically do not do it. If it is a situation in which I want someone to know they are my equal (at work, certain public situations), but as a child it was expected for me to address anyone older than I as "Mr" or "Mrs".

My parents just use to introduce everyone to me as "Mr _________" or "Ms ______", but "Yes ma'am", "No sir". I do this when I go somewhere.... Like to a store or the doctor's office and everyone who works there I address them as "ma'am or "sir", but I notice that younger people don't do this. If they go to a store, for example, and ask an employee a question. They get the answer and just move on instead of saying "thank you ma'am/sir" or any type of general respect gestures.

using first names is much more personable and engaging in the business world.

The only person I've ever mrs or mr. was teachers and professors.

My 8y/os do it..

In the '60's when the hippie culture came along.

My entire family and I still do. From my Aunt's and Uncle's to our kids and grandchildren. I'm 51 and I refer to all women initially as maam. Instinctively. The way I was raised.
Anyone elderly than I am, will always be, yessir, yes maam, until I see they are undeserving. If they are a pos then I call them their surname. Respect given, respect gained
Aaagh, the good old days. Damn, I' m old

I'm in my thirties and still address all my friends' parents by Mr and Mrs. I'd feel weird if I didn't.