I agree. That works for a lot of people.
My wife is Mescalero Apache. Her brother is a muscular fit guy. Eats extremely smart. Doesn’t drink. Works out constantly.
And is a raging type II diabetic.
A lot is just genetics.
My cousin’s husband is the same way. All of his brothers have diabetes and him. All genetic.
Genetics and race are strong factors but the most likely reason it is increasing is that those that are most susceptible, those with a family history, are developing it for lifestyle reasons.