This is really not a debate at all. Our bodies have evolved to been omnivores, however the steps.
More to the point, do go for a trip into the wilds and try to feed yourself. You will soon learn that most raw leaves are difficult at best and toxic at worst. Easier will be insect grubs. Outside the ubiquitous fig of the tropics, most fruit is terribly seasonal and will ruin quickly. All this means that actual survival must access living protein.
Certainly humanity got it biggest boost at the seashore where mussels and clams abound. From there it is simple to also harvest fish, even by hand. Going inland meant real tools. That could have been a throwing stone.
Most plants actually became properly accessible with the cooking pot. .
Were Those Who Roamed The Earth Before US Nearly All Vegetarian?
Posted on July 22, 2017
“Studies are confirming the health benefits of meat-free eating. Nowadays, plant-based eating is recognized as not only nutritionally sufficient but also as a way to reduce the risk for many chronic illnesses.”
Arjun Walia, Collective Evolution