For a person with diabetes, exercise is just as important as diet and medication. In fact, the American Diabetes Association recommends at least 30 minutes of physical activity that increases the heart rate five days per week.
Look, I don't disagree that exercise is important (I wish I'd started taking it seriously twenty or thirty years ago instead of ten) but I'd just like to point out that as a person with
T1 diabetes, absolutely the most important thing is medication, namely insulin. I'd be dead in a week without it, probably less.
. Although I may or may not be able to reduce the amount I take, via diet and/or exercise, I'm dead without it, and I don't produce any of my own.
And just as I can categorically state, as a T1, that insulin is more essential than exercise, I think that you also have to recognise that there are many different shades of T2 (and T3c and MODY and ...) out there, and some people don't fit neatly into any particular diabetic box. I wouldn't be at all surprised to hear that many T2s have their diabetes improved by exercise, (just as I'd expect most of them to have their levels improved by reducing carbs), but some have other complications or illnesses that make exercise almost impossible.
I don't think there is a one size fits all treatment in diabetes, partly because it is a condition that has so many different causes. All you can do is try to control your own particular flavour, sharing advice with others but recognising that they may be in a slightly different position.