Also - if you don't have the willpower to lose weight, wouldn't taking weight loss drugs put you at risk of relying on meds for everything? (Including stuff you might have the willpower for - now that you've tried meds, why would you ever do stuff the hard way?)
It's not easy to willpower past biology, which for many includes unbalanced hunger control mechanisms. I chose a low-carbohydrate diet to control my appetite. But if semaglutide allows people to lose weight, then it's probably better than obesity.
They probably could have been doing keto this entire time, but doctors cant prescribe it, the US Dietary Guidelines recommend against it, and the largest US medical organizations say it might kill you. Nor is it terribly difficult. But keto is not effective because of willpower, it's effective because it's chemical and metabolic and hormonal.
And it's worth remembering that obesity contributes to many other diseases and premature deaths. Treating it long term will prevent a lot of human misery and billions in healthcare costs down the road, even with the high price tag that it currently has.
Willpower is a limited resource and some people have more of it than others.