I'd call it an a-rationality quote, in the sense that it's just an observation; one backed up by evidence but with no immediate relevancy to the topic of rationality.

On second thought, it does show a kind of bias, namely the "compete-for-limited-resources" evolutionary imperative which introduced the "bias" of treating most social phenomena as zero-sum games. Bias in quotes because there is no correct baseline to compare against, tendency would probably be a better term.

Partially. It's related to how most of us are in fact biased, and taken to the extreme, the consequence of our implicit thought pattern.