You’re right. It’s the nature of things, being inclusive often means excluding an other.
On the other hand I’m glad we’ve all converted on one common reference for dates and don’t have one for each sphere of influence, cuz then something published in China vs Japan vs Taiwan vs Europe and the Americas vs Egypt vs… who knows what would be messy.
> I’m glad we’ve all converted on one common reference for dates
At least most places that use other calendars also keep track of the Western year in parallel.
My Thai wife was born 543 years after me, even though we were born in the same year. ("Hi, this is my wife, from the future!") Our wedding certificate contains only the Thai year. As I remember, for official purposes, Japan counts years of the current emperor's reign, along with an official name for each reign.
On the other hand I’m glad we’ve all converted on one common reference for dates and don’t have one for each sphere of influence, cuz then something published in China vs Japan vs Taiwan vs Europe and the Americas vs Egypt vs… who knows what would be messy.