Ok, I concede...
... It could have been part of research regarding lower wash temps, and dishwasher design. However, I simply can't see people actually following any kind of loading instructions. As whirlcool said, people want an on/off switch and that's it.
My thing is electricity. You would not believe how many people who think that whether or not an outlet is overloaded is determined by the number of items plugged into it... not what's running, not what the items are, the number of cords plugged into an outlet. That means that 6 ten watt led lights that are TURNED OFF draw more current than 3 air conditioners turned on. Worse, there is NOTHING one can say that will change their minds. The same illogic applies to circuits. It's been patiently explained to me many times over the years that I'm 'confused' because I suggest that 2 different outlets in different rooms might be on the same circuit. Now? I keep my mouth shut unless I get a clear indication the person actually wants information.
I once went to Europe with a woman who thought I was confused when I tried to explain that adapters and converters were 2 separate things. She plugged her American curling iron into an adapter and plugged it into an outlet in Hamburg. The curling iron was unaffected but she melted her hair. Did she learn? No.
I've run through my life time allotment of patience for this kind of stupidity. Now I just smile and nod.
I might notice this kind of mentality more because I'm older, but I do think there's been a shift. I think people are more resistant to thinking, more resistant to acknowledging that what they do affects outcomes, and more resistant to acknowledging that the message and the messenger are not necessarily connected.
When I was younger my friends and I frequently said, "I don't care." However, we knew that our lack of care had no effect on the thing in question. Now, for some reason, a lot of people seem to think their lack of care does. Weird.
I totally understand where whirlcool's coming from.
Jim