Agreed. This makes me wonder if a purely rational species is something that can even survive evolution. A lot of irrational behaviors we exhibit are likely the result of traits that have helped us survive in the wild.

If those traits helped us survive in the wild, they WERE rational. The point being, a fictional species that was able to widely remove once-rational but no longer rational things is the important bit. It's evidence that they have the capability, and either through a "better" society, or an extreme but likely stable authoritarian system that prioritized scientific endeavors like visiting far star systems and meeting the creatures there with no intention to harm, are able to make changes to themselves to make things better.

That is not a feature we share. We only occasionally make things better for all of humanity.