Never heard of this hypothesis, however would explain why diabetes is so damaging to blood vessels. However I think diabetes tends to be more damaging to microvasculature and isn't always associated with high blood pressure.
I think there's low risk to supplements that support nitric oxide, like arginine or citrulline. Not sure if there are others, but I think the biggest risk is to your pocketbook.
Some people report benefits. I tried citrulline for a bit as I got it pretty cheap on sale. Didn't notice much benefit, maybe marginal increase in vascularity, but that's about it. Was not taking my BP regularly though. But I think the half life of most of these isn't that long. So you might only get a few hours out of each dose.