I am not able to verify the accuracy of your calculations, but for comparison, Delta circa 2018 marketed how its entire fleet (flying at a pretty high capacity

I am not able to verify the accuracy of your calculations, but for comparison, Delta circa 2018 marketed how its entire fleet (flying at a pretty high capacity factor) averaged ~44 passenger miles per gallon. I don’t know how air freight is factored into fuel efficiency calculations, but it has become an increasing part of passenger airlines’ business models in the past decade, too. (Source: I spent way too much time keeping tabs on Delta as a top level frequent flier)