Re: so much wrong here...
Also, nearly all of the earthed/grounded variety get installed upside down because it makes them look like a face.
Actually there was no standard, hence no "upside down", prior to NECA 130-2010 and with many cords outfitted like this and wall warts like this one it made sense to have the ground pin on the bottom if for no other reason than gravity. Of course such items still exist and it isn't like anyone is going to cough up funds to mandate and inspect houses to ensure that all the electrical sockets are installed so that polarized wall warts actively work to remove themselves from the socket and have the earthing pin on top, note that few actually have a screw to retain them.
It was likely easier in the UK to switch since many appliances were delivered with bare wires and no plug and being just after WWII there was probably quite a bit of remodeling to be done anyway. Trying to convert all the appliances in the US would be near impossible on a cost basis alone as many folks can't plug things in right much less swap a plug on a power cord even if we could mandate a socket change.
I grant the UK plug is a better design albeit imperfect but then I'm dissatisfied with most electrical connectors. Don't get me started on the fact that the car cigar lighter has somehow managed to become a standard for 12V DC power. The horror, the horror.
Biting the hand that feeds IT
