I agree that blaming fat people for being fat as if it was all to do with a lack of willpower and idleness on their part is completely counterproductive.
Most fat people (including me) are fat for a number of complex reasons which include several of childhood diet and upbringing, parental relationships with food, poor knowledge of nutrition, lifestyle that isn't conducive to regular cooking/meal planning, society changing what it accepts as fat, mental health, poor self esteem leading to binge eating or secret eating - and then once you are overweight the changes in metabolism kick in and you are stuck. And that's without including illnesses like PCOS making it harder to lose weight in the first place. In the very very obese the incidence of childhood sexual abuse is high.
And that's without including the role of food manufacturers selling us high fat, high sugar products at eveery opportunity. The vast quantity of stuff I can't eat for the rest of my life is staggering. It's all around us. No wonder diets don't work. So it largely isn't the fault of fat people eating too much and sitting on their arses that they are fat.
So very far from just a lack of willpower and unlikely to be solved by just 'eat less, do more'. Took me a fuckload of counselling and a healthscare to be prepared to even try which most of the population will never get - I'm bloody lucky.