For most kinds of human systems, evolution selects for resilience, flexibility and ease of communication instead of logic and efficiency. So we end up with thin

For most kinds of human systems, evolution selects for resilience, flexibility and ease of communication instead of logic and efficiency. So we end up with things that are kind of weird but somehow remain dominant for thousands of years, while your perfectly designed alternative never gets off the ground. Metric is surely a great leap forward than what we had before.