Just because humans survive on very little protein doesn't mean there are not negative implications, notably on muscle mass and development.
just a matter of time.
Adult humans require surprisingly little protein. So little, in fact, it's virtually impossible to be protein deficient eating an adequate isocaloric diet with even a modicum of variety. This is a very well cited page which explains most misconceptions and falsehoods about protein in diet https://www.drmcdougall.com/misc/2007nl/apr/protein.htm
Survival is justification for eating animals -> These people are bad because they eat animals but could eat non-animals to survive. Are you saying survival is justified to eat animals only if there are no other things to eat?
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That something might be a plant or animal. As long as you _attempt_ to minimize the suffering of what you're consuming, then eating plants over animals isn't morally superior.
It also doesn't really matter if it's a cow, chicken or frog, as long as you're not making the animal suffer pointlessly.
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