Industrial agriculture in all its forms, including monocrop agriculture, is terrible for the environment.

"The environment" in and of itself is more complex than just emissions. Things like the water cycle and latent heat have to be considered too. Look at sustainable and regenerative farms. Ruminants regenerate the topsoil, irrigate ground naturally, and sequester carbon in the soil. This offsets their methane emissions. Also soil health and biodiversity in particular, I suspect, is something that we don't care about enough.

FWIW, I've been learning about how to become a regenerative farmer. There's a lot of learn about in terms of how one can contribute to the good of society by improving the environment around oneself. By looking for a plot for a farm, I've learned that there are laws here for land that can be used to farm crops, and land that cannot. A lot of that land can however support grazing animals.

On an aside, on the topic of "meat farming" vs plants, we should also consider essential amino acid yield and nutrient density when doing environmental impact assessments, and not just crude protein yield. Otherwise it's not really a fair comparison.