The lungs are an organs, not muscles. They improve in performance via the optimization of gas exchange in order to oxygenate the blood.
You've completely generalized the body without understanding cellular metabolism (IE energy production). What you put inside your body matters as to how the body will convert it into usable energy for work, or in this case conditioning/endurance. Consuming highly processed sugar - the absolute lowest quality form of fuel known to human biology - WILL impact the capabilities of the mitochondria within the cells to produce ATP (cellular energy), and further, WILL increase reactive oxygen species production within the cells which causes inflammation and from an athletic perspective, decreases tissue quality and performance.
Just cause you see dudes drinking gatorade on the sidelines and they still have a ripped six pack doesn't mean their bodies are functioning optimally. A guy who is taking the time to fuel his body properly is someone trying to stack the deck as much in his favor as possible - as he should (see Tom Brady, TB1 etc.) Whether all this has the desired, quantifiable impact Aaron Jones is looking for remains to be seen, but a blanket statement that your dietary intake doesn't effect athletic performance is patently incorrect, regardless of what your Phys Ed teacher might have told you 30 years ago.