I found this article dangerously misleading.
While it is true that there are no essential carbohydrates, there are essential vitamins and minerals as well as phytonutrients that are essential to optimum health which are embedded in, and transported by carbohydrates (fresh plants, that is--not doughnuts). There is a vast difference between eating plants and eating processed starches and sugar. Consuming a salad of fresh fruits or vegetables is not even vaguely like eating an equal quantity of spaghetti, for example. Both come from plants, but the pasta has nothing of value to offer, whereas the salad is bursting with healthful nutrients.
Protein and fat also can--and should be--classified as good and bad, in large part by whether they are refined and overprocessed, or close to their natural state.
Finally, it should be noted that protein, fat and other nutrients can ALL be obtained from plant sources, without having been first processed by animals (converted to meat and dairy). I've been enjoying radiant health since I stopped eating animal products, well over one year ago, so I can say this without hesitation.
I don't believe that it's carbohydrates as a chemical compound that are a threat to health, but the consumption of highly processed plant AND animal food--stripped of nutritional value and reduced to very simple sugars, damaged fats, and unnatural molecules. Because we have not co-evolved with these anomaly-ridden foods, we lack the genetic code for coping with them, let alone deriving any benefit from them.
It's not a stretch to say that people who consume even moderate amounts of highly processed food can expect to develop degenerative diseases. The current high rates of diabetes, cardiovascular disease and cancer bear this out.