I think it’s also worth considering what level of meat eating would be sustainable if we extrapolated out to everyone on earth doing it. I think we’re extremely fortunate that vegetarianism is so common in India
Vegetarianism, but not veganism - there's a LOT of cows in India - about a third of the world's bovine population, give or take.
Milk products are obviously a big part of the diet there, and it invites the question 'what are all those cows eating?'. And then some questions like 'How much beef could they be consuming in a similarly sustainable <sic> fashion?'.
If you've been to India you'd have noticed cows are everywhere. Frequently just wandering wild along the city and suburban streets.
Tangentially, a big part of India being vegetarian is obviously cultural, but I suspect that health or food safety / handling plays a (growing) part. When I travel to India my diet shifts to primarily vegetarian - just to reduce my health risks.
