That's not true at all. Today with CAFE requirements getting both stricter and harder for manufacturers to meet, both Honda and Toyota are building their engines with extremely loose fitting rings, in an effort to produce less rotational resistance. Thereby chasing minuscule increases in mileage.Better engineering and improved machining has lead to tighter tolerances and better ring seal with improved combustion efficiency, thermal efficiency, and mechanical efficiency.
We're willing to accept that modern engines aren't worn out and in need of a rebuild at 100k miles. We accept that advancements have allowed them to last much longer. Why can't we do the same with oil?
The end result is Toyota is having big problems with coking and gunking up of piston ring grooves, that are causing oil rings to freeze up, causing scored cylinder walls and destroyed engines. And Honda is having massive fuel dilution issues with gasoline contaminating crankcase oil.
Some people are complaining to dealers the odor of fuel is making them sick. And others are complaining the oil level is showing over 1 quart overfilled in as little as 1,000 miles after an oil change. Because of severe gasoline contamination of the crankcase oil.
ALL of this is from building engines LOOSER not TIGHTER. Tolerances are in fact looser, which in turn is causing worse ring sealing, not better. The exact opposite of what you are claiming. And ALL of this requires more frequent oil changes, not less.
And I don't care how great the oil is, or claims to be that you put in your engine. If it's going to get diluted with over a quart of gasoline in as little as 1,000 miles.