That’s both absolutely true and a massive distraction from the point. An environmentally friendly diet that includes meat is going to involve sustainable hunting not factory farming. In comparison an environmentally friendly vegan diet is staples of meat replacements and not trying to get fancy with it. It’s shit like beans instead of meat, tofu and tempeh when you feel fancy. It means rejecting substitutes that are too environmentally costly such as agave nectar as a sweetener (you should probably use beet or cane based sweetener instead).
So in short eat vegan like a poor vegan not like a rich person who thinks veganism is trendy