The environmental issue with raising livestock isn't that they fart. It's that they convert energy from plants to energy stored in their flesh with low efficiency, so to raise livestock, humans need to grow more plants — and use more resources — to feed the livestock than they would need to grow if the humans ate the plants directly.
I find that people concerned with animals rights tend to emphasize ethical arguments over (valid) environmental arguments, while those emphasizing the environmental arguments are genuinely concerned with the environmental cost of animal agriculture. In other words, most people making environmental arguments against animal agriculture are not trying to trick you.
I find that people concerned with animals rights tend to emphasize ethical arguments over (valid) environmental arguments, while those emphasizing the environmental arguments are genuinely concerned with the environmental cost of animal agriculture. In other words, most people making environmental arguments against animal agriculture are not trying to trick you.