Internally Excel saves it in English (or some internal code) and translates it when opened.

My company switched from Excel-Interops, where you had to send the German function name to Excel. Now we write .xlsx files directly and have to send the English function name. But when opened it displays all functions in German (or whatever localization Excel is set to).

That curtain makes everything at least twice as mysterious

And it’s not just Americans either. At least in Germany we’ve got credit agencies that rate you with their secret algorithms. Got a bad score? Sucks for you! I don’t know about having to take out loans to improve it though. I think that does the opposite. I’m not an expert, correct me if I’m wrong.