I was only commenting on the concept of free will. Doesn't matter where you apply it, we're all just following our programming.
Obviously, the program is incredibly complex, otherwise the illusion of free will wouldn't be so easy to believe.
However, there are many examples where the programming becomes apparent.
The best example of this is a radio lab episode about a woman with transient global amnesia. Her memory reset every 90 seconds, and she kept repeating the same conversation over and over for hours. Like a program stuck in a loop.
She couldn't choose to say something else. Given the same input, she would repeat the same response every time. She didn't have the ability to realize she had already said it, so she just kept looping.
"I can spend a ton of executive function thinking about and preparing food in a way contrary to what the food industry and their advertisers, food engineers, psychologist, etc., try to get a person to do while having only a slight chance at losing weight if I've already gained it. I'll probably do so by getting involved in the super scammy diet industry."
Vs
"I don't want to spend that much of my life thinking about, preparing, tracking food (maybe because I have an eating disorder/medical issue/mental health issues, maybe because it's just not worth it to me)"
It's also not just a choice, it's dozens of choices every day, forever.
You're way oversimplifying it. We're not going to magically get better humans, so maybe changing the systems would be a better way to get results than relying on people and industry to change their behavior (which is obviously not working).
Even if you only have access to garbage food you can still limit your caloric intake. I eat fast food every day I work and I'm a healthy weight. It's not difficult at all.
All you have to do is know how many calories you need in a day (this is easily available online)and keep track of how many you're eating (again nutritional info is easily available online). If you want to get really fancy with it you can look at protein/carbs/fat specifically.
Everything else comes down to self control and making excuses. If you have problems with snacking don't keep snacks in the house or at least serve them in a reasonable portion instead of sitting with the bag and shoveling them down your gullet for an hour before you realize what you've done to yourself. If you only have fast food options buy al a carte items instead of the XXL Big Mac combo with a 1/2 gallon of coke. A bit of self awareness when you are choosing what you consume is all it takes.
I've practiced CICO most of my adult life. Both when I wanted to gain weight and when I wanted to lose it. It works. The body can only reduce metabolism so much. If you maintain a deficit you will lose weight. When I'm cutting I can plan almost exactly how long it will take to get where I want to be just by tracking calories.