That's more impressive, and yet, as a non-expert, I still don't know how to evaluate whether the calculation is bug-free. Do you? I guess I'd have to track down all the references and build my own spreadsheet? There are some spreadsheets listed in the references, but it seems like a complicated task.
Just to nit-pick one little detail, it seems to treat all land the same: "Significant decreases in land occupation also follow from a shift away from animal-based foodstuffs. The VEG and VGN occupy 70% and 79% less land than the MUD, respectively (VEG = -63% and VGN = -74% for isocaloric diet comparison)."
But, prime farmland and grazing for grass-fed beef aren't the same, so adding them up and taking a percentage seems dubious. (I'm also skeptical of estimates with no margin of error.)
Given that no single scientific paper is definitive (you need to read the literature) I don't see how to come to a conclusion on any of this without a whole lot more work than I'm going to put into it for an online discussion.