in 1970 (when the US was supposed to change) if you asked me about the metric system, I would have told you the rest of the world should change to our system. Why not, I already know it.
Fast forward to 1990. I go to work for a company that has machines and tools made in Austria. Gauges read in bars, not pounds. All hardware is in MM.
Now, ask me the same question. Yes, we should change today. Metric, like our money system, is just plain easier, can be more accurate and faster to work with.