The fruits you find in your supermarket are entirely man-made through decades of cross-cultivation. They don't exist in nature. You think "Golden Delicious" apples are natural? Wild apples taste like s*** and you'd have next to zero instinct to eat them in the wild. The fruits you eat are all engineered to pack as much fructose as possible (because sugar is a highly addictive drug), and fructose like all sugars is horrendous for you and will rot your teeth (go look at all the "fruititarian" dipshits with rotting teeth in their late 20's and early 30's LOL).
The human body requires minimal amounts of carbs which it can actually produce from protein and fats through gluconeogenesis, so there goes that argument. Use some common sense; unless you came from the tropics you'd only be able to find fruits in SEASON for a few months of the year in nature. What fruits are you going to find in the dead of the Canadian winter? Watermelons? Mangos? LOL. At best these are "once in a while" food sources as evidenced by the human body's adverse digestive reactions to overeating them (diarrhea, bloating, reflux, etc) and yet your "food guides" will try and tell you that these are things that you should be loading into your diet every day when its a sheer logistical impossibility in nature, and not biologically supported either.
The digestive tract argument is far more important than the teeth argument (which is absurdly stupid). Your front teeth can in fact tear flesh. Humans also possess hands and fingers which can serve the same purpose, that other carnivores do not. Yes, you are an "omnivore", but the story that you are told is completely wrong. You are not programmed to be a 50/50 "ominivore" which is what the term seemingly implies, and even worse that is now shifting through manipulation to suggest that ~75+% of your diet should supposedly come from grains (never eat these), legumes (LOL), and plants and fruits. The bulk of your diet should come from real animal products. Every civilization in history understood this, which is why they'd value animal foods over everything else when given the option. It is virtually impossible to become overweight on a ketogenic diet, and yet in today's society with obesity and heart disease through the roof you are told to limit meat intake to things like skinless chicken breast, and load up on "heart healthy" whole grains LOL. In nature, the first things that humans consume is fat and organs as they are the most nutritious. Even herbivores like cows take plants (grass) and CONVERT it to saturated fats which they then utilize.
All you need to look at is raw human behaviour. Why is it that you find that infants, toddlers, and young children are absolutely disgusted by plants and vegetables which are supposedly "the most nutritious" foods (as you are told)? It makes no evolutionary sense for something that you are supposedly meant to survive on to taste disgusting, and that is exactly how young children view most plant matter. The only reason why people eat things like spinach, kale etc. is because they are TOLD it is "healthy". There is no biological urge to eat these plants, and alas in nature which is filled with plant matter you understand that 99+% of it is completely inedible or will make you horribly sick, whereas you can eat almost every animal known to man and draw nutrition from it...even insects.