Now a letter has been submitted to The Guardian, advocating for sustainable farming - but is there such a thing?
Farmer David Finlay is challenging Monbiot's view on animal agriculture in a letter titled Proof that sustainable meat and dairy farming can work.
In his letter, Finlay writes he is currently challenging the idea that animal agriculture is unsustainable in a three-year experiment.
"Here on our rented family farm of 100 dairy cows with some beef and sheep, we are in the first year of a three-year, final-stage experiment to challenge the idea that treating our animals, land, environment and the people who work and live here with respect is somehow incompatible with financial viability and our industry’s ability to provide adequate amounts of affordable food, and is therefore unsustainable."
Finlay goes on to elaborate that the farm uses agroecology, agroforestry, and calf-with-cow dairying practises in a bid to prove that farming can 'work'.
However, he admits that "On paper this should work. In practice it hasn't been easy."
Finlay claims he has hit targets such as cutting the use of antibiotics, anthelmintics, vaccines, soluble fertiliser, and pesticides, without compromising productivity or animal health.
On the farm, they have also increased biodiversity and reduced staff working hours.
He says they have extended the period of time the calves remain with their mothers, from 24 hours to between five and six months.
Finlay stresses: "When you see something you know is right, it’s about finding ways to make it work, not giving up."
The letter concludes: "So please, don’t bundle all farmers into the same pigeonhole, George.
"The consensus – outside of vested interests – is that there is room for meat and dairy in sustainable diets. We just have to be a good bit more selective."
But is promoting 'sustainable' farming as the saving-grace of humanity the solution to mending the planet?
If nothing, 'sustainable' and 'organic' farms are more labor intensive than conventional agriculture; and the logistical realities that come with sustainable farming can't be that feasible.
Over time, surely even productivity advantages dwindle?
And how sustainable exactly is slaughtering animals? They seem to have been missing from the argument.