In the words of Einstein "The true sign of intelligence is not knowledge but
imagination."
They are one and the same if you learn correctly. You need imagination to be intelligent, and vica versa. This is further proven by thinking about various theories. Quark theory, for example, it is almost impossible to understand this without intelligence AND imagination. Yet it exists.
Thus I negate.
The metric system is much more simplified and easy than the US customary system, it would take a while to embed into the norm, but it would be a wise decision. Considering that the metric system is a series of tens, if we grew used to it we could easily make it regular and these ideas are ignoring the fact that the rest of the world uses the metric system. This makes it a smart economic decision as well, because it makes it easier to trade anything that needs specific measurements.
It should be treated as a matter of criminal justice for the simple reason of the wording. The word illegal is so tied up with the criminal justice system that to associate it with anything else would make it legal, and by extension, off topic.