Yeah, I have no idea if gym helps everyone, but being active (on average) will yield better results than not. I was very active too - doesn't stop illness :)
That balance between all the things we are "meant" to do, is difficult for me at least. Some seem to manage their time and resources far better than I though.
That time management is a tough nut to crack for me, still have not managed since leaving home at 18, and that was a long long time ago. 40 ++ years ago.