I’m not at all saying that there isn’t a diet that works best for most people most of the time. I, personally, believe that this is the case. But there is simply no conclusive evidence in favor of any given person’s favorite diet being that diet. And the inconclusive evidence that does exist is much weaker than most people seem to think that it is.

It might make sense to you, but there is as yet no evidence for any of this, except more broad statements such as 'eating enormous bulk calories every day will probably kill you faster than not doing so'.

What are you saying/meaning by disease? Cancer is tied to length of life, and to a small degree, diet (bowel ca) and other modifiable risk factors (ie fat people have higher rates of cancer due to increased numbers of cells... which is interesting because most data says we don't produce new cells for fat, the fat cells just get bigger. So there is a mismatch there that isn't entirely explained by the data i've seen)

Osteoarthritis is clearly linked to weight, so people put their knees/hips/backs out at higher rates.

lack of exercise/modern lifestyle again ties in with the sports injuries.

On everything else, I challenge you to Prove that there is actually more disease. More disease of what? We have reduced or eliminated huge volumes of disease through vaccination and other preventable health. The other stuff is life/longevity linked, or reduced activity linked (ie T2DM/Metabolic Syndrome).

It is a very modern and pseudoscientific concern to be trying to link all this to diet. Yes, you should probably try and eat fresh stuff more than processed stuff. Yes your life should include an exercise regime. But your body is pretty good at breaking down macronutrients into micronutrients, and even though some of those micronutrients can function as drugs, there is not enough evidence to say anything too exciting here