It blossomed in the seventies. When I moved to Canada in ‘72, men did not curse around women, and women did not curse in public.
Moving back to the US five years later, it was a shock to hear pretty girl-next-door types cursing in mixed company like a sailor, completely un-self-consciously.
It’s pretty much a waste of time to treat any woman under fifty like a lady because (1. She’ll resent the courtesy, (2. She has no idea what you’re doing, (3. She can’t be bothered to get off her cell phone, anyway.
True