Obesity hasn’t been an issue since somewhere in the 1970s. And not everyone was constantly starving before then. Yeah we are predisposed to eat more than we need but we have satiety signals, unlike some animals which will literally eat until they explode.

More importantly people display self-control in other regards. Lots of obese people have become really successful, lots are genuinely tough people. People have the self-control to finish school, work, and otherwise take care of themselves (e.g. keep the house clean). Why don’t they have the self-control to choose a steak and salad instead of pizza and fries?