So in the US if you are telling someone a date you say something like 'June 5Th' (year is optional if in current year). How would people in other countries say it?
Also in all other languages where I know how to say the date it's some form of 5th (day of) June. While it is possible to have it the other way around it's really only found in old writings (June's 5th day).
5th of June or June 5th, both are valid. However numeric date format has little to do with how it's said. yyyy-MM-dd (and seperator variants) has the benefit of being orderable and indexable chronologically.
There's the wrong way and the American way. DD-MM-YYYY. And keep your weird-ass punctuation marks out of it. Looking at you whichever monsters use „ as their opening quotation marks.
Fun fact, more Americans are native English speakers than the next three countries combined. England is fifth. Which means that our way is the correct one.