You can tweak this metaphor and get plenty of real life examples. Cats are obligate carnivores. There’s been lots of morons who went vegan and decided their cats could be vegan, too. I’ll leave guessing the outcome of that as an exercise to the reader.
Yeah but he’ll change every base unit to x, so now we measure acceleration in x/x^2 and volume is measured in x^3 and the highway speed limit is 80x/(x/60).