I'd argue the oldest forms of government were probably strongmen and overbearing tribal leaders. If you stretch out the time frame, the expansion of our in-group is even more apparent.
You're right that the tendency is positive. Don't mean to be a downer. But that doesn't mean we will always be able to overcome all obstacles. And move to an utopian society. We may reach a dead end instead. Where we just don't have the capacity or ability to live in a better world. Where for example if you replace the people now in power with someone else that was oppressed, that person will then oppress others the same way. We are biological creatures. And limited after all. But it's also true that the institutions we create have influence that each person doesn't have. And it has been moving us in a positive direction. Though slowly.