The agricultural revolution - settling, understanding the seasons, plant selection and breeding - are much more important factors to where humans are today and the rise of civilisation and modern population scales than animal husbandry. That was part of the story but I've not seen any researcher arguing that domestication of the cow was more important than grains.
But anyway there is no doubt animal meat is nutritious. The question is not xis it nutritious" or "was it important for humanity in the past," the question is where we go from here. Even if you can make a cogent argument that it was essential to humanity's rise that doesn't provide an argument (or vegans might say a justification) that we still need animal meat in 2050. Arguably constant warfare and burning coal was what drove technological prowess in Europe to bring us a long way to today's world, but would you argue we still need those? Slavery was essential to the rise of America, does that make it right to continue? Colonialism made Britain rich and rose many Brits out of poverty, does that mean Britain should continue exploiting India? Domestic violence and marriage of underage girls was a common and essential feature of human societies every where, does that justify continuing them these today?
Arguments based on past practice hold no moral or scientific sway over our future.
But anyway there is no doubt animal meat is nutritious. The question is not xis it nutritious" or "was it important for humanity in the past," the question is where we go from here. Even if you can make a cogent argument that it was essential to humanity's rise that doesn't provide an argument (or vegans might say a justification) that we still need animal meat in 2050. Arguably constant warfare and burning coal was what drove technological prowess in Europe to bring us a long way to today's world, but would you argue we still need those? Slavery was essential to the rise of America, does that make it right to continue? Colonialism made Britain rich and rose many Brits out of poverty, does that mean Britain should continue exploiting India? Domestic violence and marriage of underage girls was a common and essential feature of human societies every where, does that justify continuing them these today?
Arguments based on past practice hold no moral or scientific sway over our future.