I wouldn't say it's inherently inefficient. It's certainly inefficient to devote the products of cropland to raising animals. But there's a lot of scrub land

I wouldn't say it's inherently inefficient. It's certainly inefficient to devote the products of cropland to raising animals. But there's a lot of scrub land out there that isn't suitable to intensive farming but where you can still graze cows. So from an efficiency perspective we wouldn't want to entirely eliminate meat production, just drastically curtail it. But from an animal suffering perspective and a "methane is bad" perspective maybe we do want to eliminate it.