Well we’ve had fat hate for much much longer and most attitude about fat by most people is still hate, especially by fat people themselves and that has never helped decreasing obesity.
In your example, it took clear evidence of imminent death to find the motivation to lose the weight.
I would posit that the public hate and self hate about being fat is not helping. And whenever I hear complaints about body posivity around fatness, what I think I’m hearing is the fat hate enforcers being upset at being denied. I imagine they quite like being able to hate freely and feel superior “for a good cause”.
I suspect that fat hate has never helped anyone, and probably made things worse.
I think framework of being is a personal moral failing, just doesn’t work and perpetuates the problem. Like many other “forever problems” like drug use and homelessness.
I think it’s safe to assume that problem that persist through entire lifetimes simply are bno ever going to spontaneously resolve themselves through sheer will power, especially not today where it is being sapped away by commercial interests.