This is reverse. The most potent form of keto is carnivore.
By potent I mean there are cases where only carnivore works as a solution or is a better one compared to keto (same % of fat). Highest quality protein & fat is from red ruminant meat.
The important point is to eliminate excessive carbs in the diet. And might as well do that with as little harm as possible.
Plants are subpar nutrition wise compared to red meat especially in keto.
The least harmful diet would be carnivore.
Source: 2.5+ years ketovore.
Your argument has no nuance and total certainty, which tells me you haven't thought deeply enough on the problem.
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).
Example are people with mental & auto-immune issues.