I'm not sure. Anecdotal evidence, but when I was little, we learned how to read analog clocks, and all the "half past whatever" terminology. Actually, I think most of us in my class at that time primarily used analog clocks. Even then, we never used those sorts of phrases. We would just round to the nearest 5 minutes if anyone asked.

That's still what I do nowadays. Of course, there's phones and computers now that can tell you the time, but if I want a physical clock, I prefer to get an analog one. And I still just round to the nearest 5 minutes.

In my interpretation, those phrases fell out of favor a long time ago