It’s funny that the super-American icon of the car has switched but that this hasn’t caused everyone else to switch. My image of America is a parent and child working on their car together in their garage. Would have thought that would have gotten everyone into metric over the last few decades.
I mean, over the last few decades, working on cars is harder. Maybe in part because the fastener sizes are tricky, but mostly because things are much more complex.
Anyway, the US already has the metric system for things that matter; science and most manufacturing. For things with wide reach, like distance signs, and speed limits, and quantities at the grocery store, those tend to be in customary units, because the switching cost is too high for the benefit.
As other comments have said, Why bother? Whether I use miles or km on the road is pretty much irrelevant. Everyone’s kitchens are filled with mostly US measurement stuff. And truth be told if I’m weighing things I switch effortlessly between grams and ounces on my digital scale. Some people may but I’ve no particular ideological position on it.