Well, that's definitely correct. But they do require soy, GMO soy to be precise, and monocropping is harmful, while on the other hand, cows are grazing animals, which can have a dramatic effect on the fertility of the land.

That aside, I don't believe there's a study about the environmental effect of the manufacturing of this sludge vs eating real foods.

And as an aside, the emission from cows is not as simple as it sounds: https://www.farmcarbontoolkit.org.uk/news/methane-myth-why-c...