I’d assume that if we are ever communicating with aliens and trying to figure out each other’s way of expressing numbers and doing math, dimensionless constants like pi, Euler’s number (e), the fine structure constant, etc. will be important first steps. As you say, our units of measure are purely human inventions. But the ratio of a circle’s circumference to its diameter is the same no matter what units you use to make the measurement.
To me, Fahrenheit is a lot like inches and feet for carpentry. As in it’s fine for things like describing the weather and setting my house’s thermostat. It mostly falls apart for must other things, though it’s still okay for cooking and baking. From a scientific perspective, any temperature scale that isn’t zero at absolute zero is nonsense, so it’s pretty much Kelvin or bust.