Wot about aviation?
We're still having to cope with:
feet and meters and nautical miles
for measuring distance, and
liters and US gallons and UK gallons and pounds and kilograms
for measuring fuel, and
pounds and inches and kilograms and centimeters
for measuring balance, and
knots and miles per hour and kilometers per hour
for measure speed, and so on and so on. Yes there are accidents which are partly or wholly caused by using the wrong units or getting conversions wrong.