And that's what the OEM's are counting on. As I said, it's something that won't matter to Joe Average, but the CAFE numbers matter to the OEM, so it's a win-win for them. Just because something is measurable doesn't mean it's significant, ergo, just because going thinner may accelerate wear in some areas doesn't mean that this will be of consequence to the useful life of the equipment, particularly if the tendency is for it to be taken out of service by other events/conditions.
The problem is when somebody drags out the "pile of failed engines" fallacy rather than acknowledging the nuance of the above.
Are you not familiar with the OP's inclination to run super thin oils in Super Cars that call for grades like 10W-60? If not, then I understand why you might be inclined to think that preposterous.