What if the processed-food percent of a persons diet predicts their health outcomes as well as questions like "do you exercise regularly?".

Aren't we more interested in health outcomes associated with food rather than moralistic rules or labels?

The leap from "this general rule has some exceptions" to "this is worthless" is unwarranted.

You still personally expect people that eat less processed foods to be slimmer on average than those that eat more, right?