You should check out mutual aid by pyotr kropotkin. Sure, we have several thousand years of history of the carnage of states and individuals. Thing is, humans have existed for over 100,000 years -- there is a lot missing about what our "natural" state is. Archaeological and anthropological evidence show that human societies exist on a wide spectrum of peaceful --> violent, stateless --> hierarchical.

Your implication that humans are inherently bad, cruel, competing for resources, etc. is a vestige of theory from Thomas Hobbes, connected to social darwinism, that completely ignores the observed behavior of a vast amount of animal and insect species, wherein individuals aid one another out of no apparent immediate benefit to themselves.

A somewhat famous passage from kropotkin to illustrate:

[...] to reduce animal sociability to love and sympathy means to reduce its generality and its importance, just as human ethics based upon love and personal sympathy only have contributed to narrow the comprehension of the moral feeling as a whole. It is not love to my neighbour — whom I often do not know at all — which induces me to seize a pail of water and to rush towards his house when I see it on fire; it is a far wider, even though more vague feeling or instinct of human solidarity and sociability which moves me. So it is also with animals. It is not love, and not even sympathy (understood in its proper sense) which induces a herd of ruminants or of horses to form a ring in order to resist an attack of wolves; not love which induces wolves to form a pack for hunting; not love which induces kittens or lambs to play, or a dozen of species of young birds to spend their days together in the autumn; and it is neither love nor personal sympathy which induces many thousand fallow-deer scattered over a territory as large as France to form into a score of separate herds, all marching towards a given spot, in order to cross there a river. It is a feeling infinitely wider than love or personal sympathy — an instinct that has been slowly developed among animals and men in the course of an extremely long evolution, and which has taught animals and men alike the force they can borrow from the practice of mutual aid and support, and the joys they can find in social life.

This isn't to endorse primitivism, or Rousseau's state of nature. I'm not sure I would even say "humans are innately good," necessarily. Clearly, we have the potential for evil. But the idea that capitalist competition, social darwinism, humans reveling in their own private benefit, greed, and cruelty, is natural, is both played out and nonsensical.

edit: Source https://theanarchistlibrary.org/library/petr-kropotkin-mutual-aid-a-factor-of-evolution