Let’s forget about the viability of a meat based diet for an individual and focus on two points.
Are plants killing you? Now in theory, plant defense chemicals seem like there’s something to them. But the problem is that is getting to reductionist. Who cares what these things do in isolation on a petri dish or in huge amounts given to nice? The reality is, when we look at studies across 50+ years looking at millions of individuals, those who eat more plants, ie those who eat more phytic acid rich foods, oxalate rich foods, isoflavone rich foods, etc, LIVE longer. So it’s hard to say they’re killing you. I mean hey, we all are dying, but it appears CONSISTENTLY that these foods are at least killing us, slower, than if we don’t eat them or eat less.
Viability of a meat based diet for the planet? We know on numerous metrics that meat heavy heavy diets, especially red meat, uses a lot more resources. Water, food, creates more carbon and methane emissions, and uses far more land (leading cause of deforestation).
Elimination diets open up the market of supplementation. You eliminate things in your diet and initially make the dieter feel good. Then over time the sales pitch starts. “Your getting leaky gut because you aren’t eating my flash frozen wildly nutritious liver tablets.” These supplements try to compensate for any missing nutrients. Then over time, the science community gets involved, then the sales people eventually concede that a healthy balanced approach may have been the best choice overall. But the supplement company made oodles of money and a religion that pays dividends by shaking public trust in the scientific community.
I forget which book said it: Eat real food, mostly plants, sometimes animals. Or something close. This is realistic.
For marketing purposes I love the bullshit hook of the carnivore diet:” Humans and animals have been at war since the beginning of time. “ It is hilariously dramatic and insane.