This ignores how food today isn't much like food of the past. It has all manner of added sugars and things to make it more marketable, hence higher profits, but also causes over-eating. Snack culture is pretty much an attempt to make food as addictive as possible, and many of those methods are in 'regular' food too.
Not everyone knows this and many who do can't afford an expensive farm to table whole foods diet.
Now toss in car culture and the suburban model and a culture very strongly against any sort of socialized commons like public trans and the little exercise they otherwise would get isn't available anymore. I live in a walkable neighborhood and take public trans, I know my health would be much worse if I didn't get all those steps, fresh air, sense of community, etc in everyday.
Pretty much everything Americans do is wrong when it comes to food, diet, walkable communities, and transportation. What we need to fix this is not putting everyone on ozempic, but a frank look at how our society is organized and figuring out ways to move to a saner society.