The main problem with any diet that stresses one type of food group over another is that it works against the fundamental way the body is supposed to work.
Instead of developing a new way to think and eat, one manipulates the body in potentially harmful ways.
You are talking about working against the fundamental way in which a NORMAL body works. Someone who can't lose weight, or who overreacts to excessive carbohydrates (or in my case even moderate carbohydrates) are in a different pickle. It is not possible to make blanket statements like the ones you have made. There are SOME people (and I am one of them) that does VERY WELL on a ketogenic diet,primarily because it corrects or compensates for a disorder, imbalance or fundamental problem with normal metabolism. No blanket statement regarding health, diet, nutrition, supplements, medicine or medical procedures applies to everybody. What may be extreme or inappropriate for one person could very well be the corrective therapy for another who has a very different body chemistry or metabolic bias.
My suggestion for Shawv is to read up thoroughly on the subject and educate yourself, rather than listen to people spew one line reports that are nothing more than what they read in a headline. At FR, we know to take the news and "common knowledge" with a grain of salt. This applies very much to health issues as well.