2) Is disaccharide a relevant classifier? Water is a hydrogen calcogenide, as is hydrosulfuric acid. That doesn't mean they're comparable as a food item.
It was likely chosen as a substitute for sucrose (table sugar) for being comparatively good (less bad):
> It is particularly suitable as a non-cariogenic sucrose replacement and is favorable in products for diabetics and prediabetic dispositions. [1]
Thus, the fats and proteins are likewise, in the best of circumstances, only "less bad" than sugar.
And there's such a wide variety of fatty acids and aminos that it is quite hard to generalize. Isomaltulose is probably far better than most fatty acids. And excess protein converts to sugar, too.
That's a terrible comparison. Gas is the fuel for your car, which will at some point break down to a point where you will trash it. By no definition is the gas destroying that car in the way that gas mixed with sawdust will.
> Thus, the fats and proteins are likewise, in the best of circumstances, only "less bad" than sugar.
You will die in a week without food. Some food will keep you alive longer than others. Fats and protein will do that better than sugar and protein, on aggregate. We can discuss more narrow categories within those, but it's moving goal posts from what I responded to.