Not trying to be a dick here, but do you honestly think that you, a non-expert who likely doesn’t even practice in ecology or environmental sciences, are the authority here on whether any studies have attempted to account for the water consumption based on the feed variety and sources?

Because if you thought of it as a way to shoot down a random internet comment, then the experts who work in the field have certainly done so and followed through with those calculations already. Have you ever met a professor? They fucking love to tear apart arguments because it gets their names into publications and that’s how they earn tenure and notoriety for grant funding.