We wouldn't have evolved into something like a cow without meat. Just like a huge muscle house gorilla didn't evolve into something like a cow.
I contest your point Sir, the gorilla is on the way to be the elephant of the ape world, and the chimpanzee the lion. Elephants, rhinoceri, waterbuffalo, hippos, cows, camels horses are all large strong animals, bigger than the largest carniverous land predator, and larger than the largest omniverous land predator, but they all spend all day eating, like gorillas. There are limited high nutrient food scources in the wild that are not other creatures, leading to a lack of capability to expand populations, and buffer against calamity like famine. For example nuts beans (seeds basically)and other nutritious plant food sources are only avaliable on a limited basis and timeframe, meat is avaliable all year round, otherwise carnivores wouldn't have evolved to feed off ruffage eating animals. Without animal proetin supplementing our diet we would never had the time to walk on hind legs because we would have spent all day sitting on our arzes, so in retrospect maybe were devolving.
But I think a steak once in a while never hurt.