I'm starting to have some major doubts about how much you've informed yourself on the topic here when you say "carnivore" is more foolproof than a much less restrictive diet like a plant-based diet.

You can see this just by plugging 2000 calories of meat in Cronometer and viewing the nutrition holes. Even 2000 calories of bagels gives you a wider assortment of nutrients than 2000 calories of beef.