> Everyone thinks they eat good food.
Yes, probably including you.
I am very aware of things like cooked spinach v.s. non cooked spinach. I pay close attention to what I eat, and make an effort not to fall into the traps of fad diets.
I eat a whole foods based, well rounded diet, that avoids known "gotchas" like aforementioned raw spinach. Oxalate are found in many of other "healthy" foods. I'm also very lean, but still pay close attention to the role of inflammation caused by insulin, and generally do my best to keep that down by avoiding carbs and sugar (though, not completely cut out, I am not keto).
Trust me, food is not the panacea of health that everyone espouses it to be. If you were dying of cancer, even the best diet on earth for you, may not save you. That said, a life of healthy eating is definitely a good idea and there's always the chance that I would feel worse, or simply die of a heart attack, if I weren't paying attention to my diet.
Diet is absolutely important to get in check, just like exercise. But it's all too often prescribed as THE solution above everything else. This often comes in the form of some revelation someone had, visa vi some weight lost, or some medical situation from their prior eating.
For some of us, there is no issue with weight, no medical problems, we cook all our own food (never eat out), eat well balanced whole foods, and yet still life is not magically solved.