Do you have an opinion concerning whether this is better characterized as "non-response to the benefits of exercise due to pathology" vs. "immunity to the harmful effects of a sedentary lifestyle"?

Basically, is being a non-responder good or bad? Eyeballing that graph it does look like untrained non-responders might be a bit fitter than responders - but of course the first thing we should assume is ceiling effect.

(And of course there's many 3rd options - orchid/dandelion trade offs and such)