Fair. But the point is that it follows the only reasonable order, consistently from larger units to smaller.

A datetime can be seen as a number written in a positional notation, just with varying base: divmod by 60, 60, 24, 12. When you pick a normal decimal / hex / binary number, you expect that the digits in it come in the order of magnitude changing: thousands, hundreds, tens, ones. Mixing them would feel crazy. By the same token, formats like dd-mm-yyyy HH:MM or mm-dd-yyyy are crazy; sadly they are traditional.