I agree this horse has been run hard and put up wet too many times. But if you notice how many home appliance makers use a cord with the u-gnd molded in the down position. Refrigerators and freezers are good examples. If the u-gnd is in the up position on the receptacle then the cord will have an unusual sharp bend in it. This stress in the backward position will eventually cause a home-owner to call a good electrician to replace the cord. That's where you guys come in.
Why do these manufacturers make the cords that way? Others use a straight plug which can be turned either way. I just don't know how to figure it all out.
We had an experience at our house with the molded plug with the u-gnd down. It was on a fish tank piece of equipment which was on a desk against the wall. One of our grandchildren pushed some pennies of the bvack of the desk. So happens the plug was not seated tight to the receptacle and a penny fell in behind and onto the hot and neutral. My circuit breaker did trip. It took several times around the house to find that one. Had the u-gnd been in the up position, then the penny would have just rolled off without touching any other pole.
So there are arguments still remaining for either application.