In the sense that at least for Type II diabetes, the process is gradual, and the common Western diet, coupled with the insulin resistance of age, and the still present adaptations we made evolutionarily to exist in a feast or famine state (which means most of us are programmed to store fat easily)--maybe.

Exceptions might be people of certain genetic profiles or heavy exercisers. Certainly, the idea that heavy physical work, less available food, and especially, a shortened lifespan kept many people from developing noticeable insulin resistance--the precursor to type II--in bygone eras has been advanced before.

The more interesting question may be: are all/most people with idiopathic neuropathy likely to be pre-diabetic, at least? That theory has also been promulgated, and there's been some sharp debate. Certainly, a greater number of people with neuropathy than without it have been surveyed to have some sort of glucose/insulin dysfunction. But there are also many "idiopathics" without direct evidence of it.

I personally suspect that glucose dysregulation is one of three major conditions that are suspect in "idiopathic neuropathy"--the other two are as yet undescribed autoimmune mechanisms, and, as the human genome unravelling seems to be showing, dysfunctional genetic mutation.