It has nothing to do with standardization. With science and technology today, it is not possible to work in conditions with measurements and units random, based on parts of the body of a dead king centuries ago and not even, what is more serious, does not differentiate between weight and mass. Besides, it requires complicated conversions, a source of errors. For example of calculating the angular momentum in different parts of a 1.6 mile long bridge, if it has to be calculated with inches. No problem in a Bridge of 2,364 km to use Meters, centimetros or even Milimetros, only have to move the coma, no calculations needed. The important thing in science is that the units are repeatable and reconstructible, which in degrees Celsius is not a problem, having as a reference the freezing and boiling of water at sea level as a reference. A similar reference for Fahrenheit does not exist, at least not with sufficient accuracy, which is why it was discarded as a unit. You can be sure that the manufacturers that supply Fahrenheit thermometers to the US calibrate them using Celsius or Kelvin, then put the Fahrenheit scale after converting the values.