The people you expect to know better are often the worse indoctrinated.
You are right, of course. It would help if we changed the name of this disease from "diabetes" to "carbohydrate intolerance."
And, by the way, there is an excellent web site that deals with these very issues. I recommend it highly:
I have t2d. It’s simple. If it makes your blood sugar go up over 100, don’t eat that. (or eat way way way less of that!)