I feel like you didn't read the whole of their comment.

Thanks for the apology! It can be difficult to convey tone over text.

You may be surprised to hear that lots of people actually believe the position you were sarcastically presenting! Glad you're not one of them.

Your cynicism is not only unhelpful but also inaccurate.

it's already in use for mm/dd/yyyy

No, it's already in use for dd/mm/yyyy. When the majority of the world sees slashes (with the four-digit year at the end), they expect that. Americans are the ones making things ambiguous.