>It’s hard to explain in words just how frustrating this M/D/Y madness is to everyone else in the world. There is just no sane way to tell what a date is referring to if it has numbers less than 13 for the day part. It becomes a wild guess.

Those criticism apply to both MM/DD/YYYY and DD/MM/YYYY. (MM/DD/YY and DD/MM/YY are even worse.)

>> Some people promote YYYYY-MM-DD though, which I guess is more future proof

>It’s the only unambiguous, sortable, sane format and the use of anything else should be deprecated on the web.

Are you talking about YYYYY-MM-DD or YYYY-MM-DD? They're both unambiguous and sortable. (Not sortable with the other one though.)