There's another reason George, another reason

Bucolic romanticism might seem harmless. But it leads, if enacted, to hunger, ecological destruction or both, on a vast scale.

This is entirely true. George Monbiot is talking about:

Farming in Transylvania looks (or did until recently) just as it “ought” to look: tiny villages where cows with their calves, ducks with their ducklings and cats with their kittens share the dirt road with ruddy-cheeked farmers driving horses and carts; alpine pastures where sheep graze and people scythe the grass and build conical haystacks. In other words, as the king remarked, it looks like a children’s book.

That other reason being that this bucolic romanticism is also the same thing as gross and abject poverty. Really, truly vile standards of living. Which is why absolutely every human society that has been able to abandons it as soon as possible. We are talking of lifestyles of £2,000, perhaps £3,000 a year instead of the £30,000 enjoyed (that is about the median in today’s UK) here. A tenth and worse of today’s living that is. And yes, obviously, that is already correcting for the costs of things over time and geography.

The problem with peasant farming, as with peasantry as a whole, is that peasants are poor, really, really, poor.

This, of course, being why the British peasantry flocked in their hundreds of thousands to the dark Satanic mills as soon as the option was available. The people who‘d done that backbreaking work for small reward weren’t going to do it for a moment longer than absolutely necessary.