"It is a colorless, odorless, sweet-tasting, viscous liquid." ... "It is also widely used as a sweetener in the food industry and as a humectant in pharmaceutical formulations."

https://en.wikipedia.org/wiki/Glycerol

As I understand it, they aren't saying "it isn't sweet".

They are saying "it isn't labelled as an artificial sweetener"

The key part being "labelled as".

It’s getting lumped in the wrong category here.

SimplyProtein Crispy Bars have it (Costco) if anyone wants to look in their cupboard at a nutrition label. It falls into total carbohydrates but not Total sugar, despite being a sugar alcohol. It has the same calories as sugar; but a different metabolic pathway.

Glycerine / Glycerol is NOT a calorie free sweetener. It also tastes less sweet than other sugars.

It's not considered an "artificial sweetener" as it's usually extracted from natural sources.

It also has the same calories (or more) than sugar. It’s not used to make low calorie food.

Yeah but it's orders of magnitude more sweet then regular sugar, so you use way less of it

The point is: On the ingredients label, it is called a "Humectant", not a sweetener, so a drink sweetened with only glycerol will be advertised as sugarfree, and "artificial sweetener free"