Is it easy? Fuck no. Do different bodies react in different ways? Of course. Is there nuance involved in making sure your body reacts optimally for weight loss? Of course Are most overweight people consuming gargantuan proportions of shit? You better fucking believe it.
If you live a sedentary lifestyle and consume many thousands of calories a day, fixing the problem isn't rocket science. Pretty fucking simple, and pretty fucking hard.
The fact that I am a fucking lardass is not conventional wisdom, nor has it essentially shown to be wrong. It is a simple fact. No idea what you were trying to get at there.