There's some sleight of hand going on here. You can have pasture-raised chickens and pigs (with similar soil benefits; chickens are great at picking out pesky bugs, too), and you can have factory-farmed cows in feed lots.

You _can_, but pasture chicken and pigs aren’t cheap and aren’t really done at a commercial scale. Whereas many conventional beef farmers still raise cows on pasture.

Overall, pasture chicken requires a lot of land and has soil loading issues (too many and the soil gets burned out when the balance of minerals goes off kilter). It’s much harder to overload cows on pasture - it’s obvious when a field is overgrazed.

Pasture pigs are labour intensive, too.

I'd be very interested in some literature about the points you raised.

The idea is to reduce meat overall, when I said "subsidize CO2 efficient foods", I was mostly talking about fruits, vegetables, grain, ... who reduce emissions and soil pollution by another order of magnitude compared to chicken and hogs. It also reduces antibiotics uses which is a plus.

Growing fruits, vegetables, and grain without raising animals as well means mineral inputs which are derived via mining and fossil fuel sources. This is indeed “emissions” and over the long term eventually results in soil depleted of nutrients, alongside significant ecological harm from runoff from artificially added fertilisers and other inputs.

Industrial scale grain farming also means heavy use of machinery which, again, all runs on fossil fuels. Whereas pasture raised cattle requires far less of these sort of inputs. A balanced approach to agriculture recognises the important of pasture animals such as ruminants and also recognises the damage excessive row crop farming causes.