The US style also has much smaller and cheaper plugs, and the cords are all basically the same size anyway. I don’t recall any UK appliances being notably less bulky or anything either (though when running 220v, you can have electric kettles which aren’t lame, which is nice).

Notably, pretty much everywhere else in the world also uses similar branch circuit type designs and 220v and their plugs and appliances are also not notably more bulky either.

The difference in wire diameter between say 6amps and 15 amps isn’t that noticeable. 15 and 30 is.