Healing is not the same as cleansing.
If you can fight a diseases by cleansing on juicing, it doesn't mean you can live just on vegetables for years.
Healing is usually both cleansing and nourishing. juicing and bone broth is both cleansing and nourishing. Personally, I healed my gut inflammation with bone broth and cleansed my liver with juices.
"Food is just calories, proteins, carbohydrates, fats, fiber, vitamins, minerals, enzymes"
In the Western modern world maybe, but any traditional practitioner in the East of the globe would see foods from a phenomenological point first: energy, hot/cold, light/heavy, etc. If you learned something through formal western education, it doesn't mean that it the only applicable concept. Ask a random Chinese person which food has more energy/or life force in it - broccoli or chicken? Or ask a Ukranian to compare bacon and spinach... Or a Polish person to see if cabbage has more nutritional, or healing value than kebasa (sausage). :)
"And vegetables and fruits have far more enzymes, minerals, fibers and vitamins than any animal flesh".
Wrong, animal products are much more dense in vitamins, minerals and even enzymes. Modern propaganda has taught us wrong, corn industry is much more profitable than raising chicken:) Fibers are not essential to human digestion. Good (for a healthy gut), but not vital.