You know that they discussed going Metric over 170 years in UK? Happened around 20 years ago.
It was a relief!
1965 actually (well that's when it started, we were dragged in inch by inch). Of course, we still measure speed in miles per hour and fuel consumption in miles per gallon! However, UK scientists were at the forefront of developing metric systems of measurement for science and engineering in the 1800's.
Unfortunately, I was at school in North Africa using the metric system then came back to the UK and didn't stand a chance - 12 inches to a foot? 16 oz to a lb? then 14 lb to a stone!!!! insane.
If I'm doing woodwork I will still occasionally flip my rule over and use the inches scale if it's more convenient