For broad definitions of "metric." I've got a goodly collection of British recipes that call out temperatures as "gas mark 4" and if you've never read a cake recipe designed for the Aga do-si-do you're missing out.

Speaking as someone who has now dealt with European cars, European jewelry and European watchmaking, European adoption of the metric system is far more ambivalent than most Americans realize. Jewelry is still built in gauges which are bizarrely tied to American, English or French inches, and the entire Swiss watch industry adopted the ligne despite the fact that the Metric System was 100 years old before any of them got started.

I do my casting with investment recipes that are called out in pounds and cups for flasks that are measured in inches which go into a kiln whose burnout schedules are in fahrenheit to pour molten metal melted in celsius. The only thing that makes it work is a 4-tab Excel spreadsheet with lookup tables that prints out a worksheet.

The Metric System is obviously superior on every possible level yet for some reason Europe, which has had two hundred fucking years of supposed adoption, still throws a fuckin' pouce in there every now and then just to be French about it.