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
Converting between mass and volume measures only gives 1:1 ratios when you’re working with distilled water at standard temperatures. 1 cubic centimeter of distilled water is one gram.
Doesn’t work for jet fuel or milk or depleted uranium or any other substance you might be working with.
For the miles/yards thing: the circumstances where you need the length of a mile, you rarely need the accuracy of a yard, and vice versa. You just use the unit whose accuracy you need. For example, a builder wouldn’t measure 3 yards 1 foot 2 inches. They’d just use 122 inches.
I think some of this might be right but I expect much more people to calculate/estimate more regularly than they are measuring. And if you are working fully in numbers metric seems much more reasonable. You can easily calculate without converting and even if you have mixed units you can just throw in 10^-+N very simply.