I am not a doctor. This is what I have learned so far (there are no references here - sorry, I will need to dig up the material to substantiate this if you ask):
The upshot:
Managing diet is not sufficient (for type 2) remission. The damage is at cellular level. That damage needs to be reversed. Therefore muscles need to be rebuilt. Even for the over 60 years!
The thinking:
Diabetes Type 2 is the end point of years of abuse the body endures with elevated insulin and the _extent_ of insulin resistance the body progresses to. Diabetes therefore is a spectrum - the end point is when the pancreas bonks out and refuses to produce any more insulin. It's a tiny tiny organ and I think it's fragile. And it's threshold is also genetically determined. The interesting thing is that we all (including healthy folks) have levels and sometimes acute bouts of insulin resistance! The thing that made sense to me, reading about this, was that insulin resistance is a function of your muscle cells denying entry to glucose. And the insulin concentration in the bloodstream is a direct function of the concentration of free flowing glucose. Poor Pancreas is only doing its job but the muscles are not taking in any new glucose. They are refusing (resistant). Pancreas tries its best by pumping more insulin and for longer but the adamant muscles are the contract breakers in this arrangement - they don't open the gates for glucose.
The only way to change direction permanently in type 2 is to rebuild muscles which will have better insulin receptors to allow glucose to be shunted into the cells. For this to happen you have to do strength training. Lift sufficiently heavy. (No, not Arnie levels by any measure.)
(I recently read a study that administering testosterone to type 2 diabetics improved their insulin resistance. What happens with testosterone and anabolic steroids? New muscles, that's what.)