If I may “argue to agree with you” as it were, being pro-social is absolutely our default state. We’re literally evolved to play nice with each other because that’s how we’ve made it this far. In addition to the obvious edge of big brains, any anthropologist will tell you that the human superpower is social cooperation. We do that better than all other primates and it’s probably mostly why Homo Sapiens came out on top. Evidence is now strong that we didn’t “out compete” other human species like Neanderthal, we “out cooperated” them, effectively. We bred with them, probably integrated them into our groups, etc. We built better villages, hunted better in groups, and eventually cooperation and work specialization led to the technology curve we’re on now. It’s all about cooperation.
Humans form huge cities relatively easily. Hundreds of millions of individuals who don’t know each other, living meters apart and mostly getting along their entire lives. That’s incredible. There are virtually no other animals that can manage that apart from some colonial insects (who arguably aren’t really individuals).
People always talk about humanity being all about war. I hate that narrative because it’s clearly and obviously the exception. Yes we fight a lot of wars, but it’s the tiny majority of most human social groups throughout most of history. There’s always a bunch of wars happening somewhere, but for any given group, most spend most of their lives cooperating with everyone around them.
That’s a default state if I ever saw one.
Edit: I see that @chenille already said the same thing, but much more concisely. 
