Earlier quoted context omitted.
And other people choose to wash dishes by hand and they're fine with it and not significantly less productive. The use of a dishwasher wasn't forced on everyone.
It's actually less productive for dishwasher-safe dishes, there's simply no question about that. Hand-washing dishes also, from what I understand, uses more energy and water than the dishwasher does.
Modern high-efficiency dishwashers probably beat the most efficient humans now, but that's relatively recent and not a huge margin (and may not get the same results).