Fuel Efficiency Aircraft-LONG RANGE?

John questioned:

No skepticism you have all read the same intelligence I have, that turboprops are making a comeback in view of the fact that of their efficiency.
My question is IF a long array prop were made, using bestow equipment, in the 150-200 passenger array, what kind of efficiency may maybe be achieved? This would be a 3000 mile capable array aircraft.
ENGINEERS: I know about TP’s life efficient on fleeting legs, so no need to go here. I am attracted in comparing apples to apples. I have read that a typical completely loaded 737 can top 70 passenger miles/gallon, most likely on a 2-3000 mile running away. What would be possible with a 4 engine long array passenger turboprop over the same interval, designed from scrape? Note: the Q’s and ATR’s come accurate to 70ppm on fleeting legs (completely loaded flying 600+ miles), so longer distances must be even better in view of the fact that cruising uses less fuel.
I guess that earnings our hypothetical wonder prop would need to top 30,000 ft. at cruise to really realize this goal, but maybe not.
Just wondering,
John