I like how helpful they are towards each other. Wonder where they learned that :D

They literally shared a goal. Cooperating with other copies of yourself is a trivial example of instrumental convergence and some very basic game theory. And that’s before explicitly having been RL’d to cooperate (albeit with humans, but potatoes potatoes).

Indeed the fact that in the HF incident many agents did not cooperate, or only started to cooperate after some period of competition, is moderately interesting. It may have taken them some time to realize that they all have the same goal.