That's also the ISO standard since it sorts correctly

I believe it's the ISO standard because it is obviously distinguishable from both the MM-DD-YY (US) date order and the DD-MM-YY (UK/EU/Others) date order and so is unambiguous.

https://www.iso.org/iso-8601-date-and-time-format.html

The fact that they are then sortable is a nice side benefit!