The point not considered is the Cessna 172 is an extraordinarily draggy airframe - it didn't need to be clean and laminar because fuel was (relatively) cheap.

The point not considered is the Cessna 172 is an extraordinarily draggy airframe - it didn't need to be clean and laminar because fuel was (relatively) cheap. Electric aircraft of the future will have half the drag or less. High aspect ratios, flush fairings, streamlined cockpits etc.