Haven't read whole thread.
I don't eat a low-carb diet. I eat all food groups, in moderation. My weight has always been stable and my BMI is 21-22 (only varies by the odd kilo).
I don't claim to know or understand about low-carb diets but my instincts tell me that cutting out whole food groups is difficult, logistically. And I have always felt that anything involving deprivation is unsustainable.
BUT I probably don't eat that many carbs. I always eat wholemeal bread (2 slices a day), sugar-free muesli for breakfast with lots of nuts, and pasta/potatoes/rice do figure in my diet every day but not as a the biggest thing on the plate. I eat tons of veg, cannot imagine giving up fruit (that I love) and I aim to eat protein with every meal or snack.
All of the above is focussed on eating a healthy balanced diet and I guess that it works for me because my weight is stable and healthy.
I don't want to disregard low-carb diets because I have never tried one, but I wanted to offer another perspective.
FWIW I never count calories or "diet" in any deliberate way. I guess I am busy and active and have never been an emotional eater.