There are still those amongst us who appear challenged by the decimal point. It can be as confusing as fractions and counting in 12’s? Reality is there are instances where we still need to accept or understand there are differences. Some everyday items still contain engineering that in imperial is a whole number or neat fraction, which needs to be represented in 5 digits as micrometers when converted!
Yes, an all SI world and single ISO standard would be wonderful.
I was being enlightened when we went metric and decimal. My text books were a blend of SI and American imperial units! The rules of thumb and everyday trades all worked in imperial.
There are still remnants of those days all around us. I still need two sets of tools to cover metric and imperial dimensioned equipment. Some of which if made for the US market is still very much in the 1950’s.
Ford pattern wheel studs? Golf buggy wheel rims?