Here is another vegan video that I have checked out. Take a look for yourself. This guy is arguing in support of humans as vegans (it appears). In all honesty I think that the evolutionary argument goes towards humans being ominvores. This guy even says that "typically" and "generally" carnivores are like this ... Then he goes on to explain something that is typical of carnivores. It could start to head towards being convinced if he were talking about omnivores, and if he could say that ALL carnivores are a certain way. His whole proposed discourse is somewhat of an ignoratio illenchi. He is focusing on the wrong issue.
Anyway, the whole topic of what humans naturally are, evolutionarily speaking, is irrelevant in telling us what we ought to do. That is unless vegan diet has tremendously adverse effects on human health, when done on properly. I have never seen evidence that this is necessarily the case. That does not mean that it does not exist, but the people I have read (or listened to) that try to shoot down veganism are definitely barking up the wrong tree.
We carry the gift and the burden of being moral beings. That is something exclusive to humans as far as we know, at least to the extent that some of us can reason to morality.
I don't see why vegans keep engaging in this discussion. It is irrelevant for our cause, except in trying to meet in an antiquated arena for discourse. Two of the best words in the vegan vocabulary are: "naturalistic fallacy".