Makes great sense. Each of us has a unique fingerprint, lip print, Iris print. Our compete genetic blueprint in a drop of blood. Your blood type is responsible for your internal chemistry, your immunity,your susceptibility to disease, your reaction to stress etc. So different diets and exercises for different types is very logical.
We need to celebrate our diversity our differences and our diets.
It brings into question mass medication. How can one medication suit everyone? Simply put it can't. Some people can tolerate medications that others can't. Nothing is a one size fits all.