That's amazing to see. I'm not disputing the fact that low carb works. I use relatively low carb myself and have seen similar benefits in weight loss (~50 lbs peak to trough). I think for lots of people compliance to an energy balance is easier with low carb. IE its easier to make a lifestyle change and doesn't feel restrictive or like dieting when you can eat steaks, chicken thighs, lamb chops, fatty fish, pork loin, and even bacon in the context of a whole food high fat low carb diet. The reverse is often times difficult to make ie: chicken breast, lean cuts of steak, lean cuts of pork with high non sauce covered carbs. That often times is not an appealing combo. Therefore I think the compliance to an energy balanced whole food diet is easier with LCHF and is why I follow a similar diet. The other thing is if people try to eat a balanced carb/fat diet it's very difficult for people to accurately gauge their total caloric intake per the precision nutrition article.
Anyhow, I'm largely in agreement with you Vince that LCHF can work. I just don't think its right to say carbs are evil because LCHF works. I'd also wager that the people you refer to walking around that are overweight who eat loads of carbs are eating highly processed carbs that are caloric rich nutrient devoid and have no satiety element. Example typical store brand chips, ice creams, cakes, pies, pastries......Those can and will lead to overeating.