I'm firmly in the camp that exercise is extremely beneficial. Likely one of the most beneficial things one can do (with not smoking and eating a diet high in fruits/veggies low in processed carbs).

We (society/physicians/etc) need tools to get people to exercise. This is more a study of how effective one of those tools might be (ie supervised exercise vs recommendations). If supervised exercise is no better than recommendations, I find that pretty disappointing. Because as we all know, recommendations don't work very well, or at least most people don't adhere to them.