Sure this is a fairly recent one. It makes intuitive Sense on the surface that going pure vegetarian would be beneficial and reduce emissions. But that’s because we are comparing it to a system of meat that is based off the current demand where a majority of people are large consumers of it regularly.
Animals can be beneficial environmentally speaking even when raised for food, and the resource cost for growing vegetarian food can end up becoming quite large when you scale it to that same level.
Extremes are rarely the true solution there is usually a middle ground this is no exception