I'm going to make a guess that adding in healthy eating and demanding exercise has some of us producing hormones and things that we haven't seen since our youth.
Especially those of us that were sedentary and following poor dietary guidelines.
Anyway, whether the body will adapt and stop producing "bacne" is a question I can't answer.
On a related note, I never had any real acne in my life, but I do notice that covered sweaty skin does tend to develop issues from time to time.
Interesting, a lot of my "reactions" tend to be on the boundary between lean and non-lean areas... so I like to think it means I'm leaning out (whether or not it is true is another story).