Sharp teeth to cut and hold, flat surfaces to grind. The more vege diet, the more flat teeth, the more strictly carnivore, the more sharp teeth only.
If there are only a few flat teeth, can be Omni, but need at least one set of flats to grind. If there are no flats, cannot grind. So, if no flats, then needs to ferment to eat veggies, cannot grind to increase surface area of the food.
I'm with you on the generalities of tooth structure and diet. However, not all herbivores masticate.
For examples, many bird species eat seeds whole, and digest them in their gizzards with various hard bits like rocks, shells, etc.
I just wish they would state that it's assumed or reasonably concluded, instead claiming conjecture as obvious fact, to wit: "It was indeed better not to cross the way of this large, carnivorous dinosaur," said paleontologist Christophe Hendrickx