Yes, and I do believe every individual person will have a different diet that will be the most beneficial to that individual. I do not discount the experience of anyone. If someone eats a diet of raw meat and they feel great on they diet, I don't discount that experience, but I will debate if they tell everyone that they also have to only eat raw meat. To respond to your other post, I agree that just because we have taste buds that can receive the sweet taste, it doesn't mean every single human has to eat carbohydrates to thrive. Yes the human body is amazing and very adaptable, but our taste buds do tell us, generally, what kind of foods humans are meant to eat to be healthy and balanced in mind and body and those are foods will have sweet, sour, salty, bitter and savory tastes.
By the way, I don't think it is correct that diabetics should not eat fruit. All fruit is not created equal. Fruits like dates, figs, bananas and other fruits that have a pure sweet taste may not be good for those with diabetes, but other fruits such as apples, pears, and all types of berries can be beneficial for those with diabetes. Apples and pears, even though they do contain a large amount of fructose, also have a large amount of astringency in their tastes that, in a sense counteract the sweetness. It is physically impossible to gain weight by eating raw apples (cooked with added Sugar is another thing completely because cooking apples removes much of the astringency). Every food has a unique energy signature that will have a specific impact on the body. Paleo-diet gurus and most other diet gurus reveal their ignorance very quickly when they say a perfectly healthy food is unfit for human consumption. If we instead teach about food and what the impact of a certain food is on the human body, that is a much more beneficial discussion. Of course, there are some modern foods that do deserve to be vilified.