What sayings seem to have disappeared with the younger generation?

My daughters are 25 and 23. Over the weekend I mentioned that my elder daughter was ‘talking on the big white telephone’. She had no idea what I meant so I had to explain it (being sick). Then my husband mentioned a rugby player falling on his mush (face) and she didn’t know that one either. I was quite surprised as the first one especially was always very common. I’m from Wales and wouldn’t have thought the first one was down to locality - second one possibly