Valid arguments tbh. In the struggles between European and Native American, there is the aspect of being able to escape and continue to pose as a threat and such. There is no total extinction. But in dark forest theory there is the total extinction of home planet aspect, without giving in your own location (no vengeance or kill switch can be carried towards you). And also attack factor being so much more advanced that there is little to no defense against it.

In our world, we never had this level of capability amassed in one hand. We were never tested in this scale. But lets think there was a button in cold war that completely erased soviets with no harm to planet, no harm to the western world and without anyone noticing the origin of this action. How many in U.S. would press that button? I think we would've pressed many times. And later, to know that another planet might be having a button exactly like this that they can press and erase us? we would press first so they never get the chance to do it. Paranoia and self preservation prevails, sadly.

I believe our cooperation in society also relies on our capability of projecting power be it physical or economical. The weaker individuals power becomes, the louder powerful peoples actions become. Saying this as Non-U.S citizen, right now the richest guy can easily interfere in state dealings, act like the president in a way, maybe this is evolution of lobbying tradition there but could you imagine such a thing happening in ancient Greece or even in Rome? What prevented this was citizens' ability to exert power. Right now there is little of that, power disparity is huge and so there isn't as much of a cooperation. Sorry if this part deviated from topic or smth. It is just I believe it 100% depends on real, physical factors rather than how advanced we get mentally.