JFC, walk through ANY grocery store in the US today and pick up an item and look at the label - it's dual labeled. Look at your speedometer in your vehicle, push a button and get metric. Very few people need to own both SAE and Metric tools anymore. I own 2 JD tractors and a JD skidsteer, a JD Gator ute and 2 Chrysler vehicles, all metric. The ONLY time I reach for the SAE set anymore is when I need to work on my 1941 "H" Farmall tractor or some other farm implement that was built before 2015.

And with all the digital displays on everything today, the metric system is a mere button push away. Push the damn button if you want metric OR US Customary - I do and then get the units I want for the task at hand. Ain't no one going to care about it. G20/G21, the machines don't care anymore, why should you.

The dual speed limit signs were a bad idea - they were confusing and hard to read. It was a bad design that caused issues for drivers. But, while it could be done a lot easier today, no one really cares about the miles vs kilometers. All anyone really cares about is "how long will it take to get there".

The metrication of the US is here and has been for a good while. It's become common enough you don't notice it anymore.