Even young people who have been educated in metric state their hight in feet and their weight in stone. Why would they use metric? No-one would know what they are on about!
No-one? Not even all those who have been educated in metric units? I fear you are merely talking about my (our?) generation. I remember my grandparents being in denial over decimalisation of
UK▸ currency and my parents fighting centigrade (as then known). We will go the way of all flesh and in due time the stone and the yard will become as quaint as the perch the ducat is today.
Meanwhile, in the same way as I can buy my petrol in litres and measure consumption in miles per gallon, we will live with split personalities over measurement. The one thing I want to be sure of when I am on a train is that those who are maintaining and operating the equipment are highly educated in whatever measurements they choose to use so I am safely delivered to my destination.