[steamrolled]

Yeah, and given that the mistake is consistent between the text and the image, I think the author just sort of doesn't understand inductors.

"The efficiency numbers aren’t based on calculations or research – I merely ran each circuit in the excellent Lush Projects simulator [SIM] and recorded the numbers it gave me."

I don't want to diss people for writing about stuff as they learn, but I wouldn't take this article too seriously. You can theoretically achieve very high efficiency with basic architectures. The main problem is that you typically also want to make the device small and cheap.