[bergoid]

FTA: "Faster-growing, rapacious societies might peter out before they could touch all the stars."

I don't get this reasoning. The way I see it: every solar system that gets settled is a fresh roll of the dice. Every newly colonized system increases the odds that at least one of these settlements will not self-destruct.

Polynesia is a great analogy. While Easter Island is suffering, Hawaiʻi, Tahiti and hundreds of other islands might still be going strong.

[maze-le]

That is if it is somehow economically feasibly for those societies to develop interstellar travel in the first place. When a civilization is occupied with its own struggles and conflicts (the fast-living rapacious ones), they might be incentivized to first exploit local resources before interstellar travel is considered seriously.