Not listing alternate units second, not converted on screen, not called “freedom units” and not hiding behind the excuse of “most our audience is in the US”
Mostly thinking YT channels like Wendover, Bluejay, sometimes Practical Engineering and even some European ones like TLDR News
The difference between a meter and yard is less than that of a measured vs “eyeballed” yard and everybody knows what 0 C and 100 C are so the learning curve is also massively (by at least 50 kg) exaggerated
In a duodecimal number system, metric would be absolutely gorgeous. We’d even have a metric unit circle: Each position on a standard clock would be represented by a single digit, and those positions line up with the most important angles in geometry.
Base-10 is the ugliest part of metric. 10 sucks.