Recommending a harmful diet for most people in order to treat very specific diseases (when a minuscule number of people are affected) is pretty irresponsible.
Your argument has no nuance and total certainty, which tells me you haven't thought deeply enough on the problem.
You're too focused on carnivore being harmful when you yourself recommended the keto diet. I never said to go carnivore, just that it's better. I don't do it myself mostly for it's harder to maintain when traveling & stuff.
If you were just a bit interested in how keto really works and had a curiosity on advanced cases or followed pros on twitter you'd agree with me (losing weight is easy compared to fixing epilepsy/schizophrenia).
Plants are subpar nutrition wise compared to red meat especially in keto.
The least harmful diet would be carnivore.
Source: 2.5+ years ketovore.