... were our imperiled heroes save their 'hinds by locating and jerryrigging a defunct piece of hardware that was left behind from a previous mission?

This is half the answer, though we'd also need those indicators to be plentiful and compelling.

> we know very well how personal behavior is distorted

This points to the other half: humans are irrational by default. We tend to believe what we "experience" - see, hear, etc. - even if we know it's a lie. Have you seen those videos of people in VR glasses panicking as if they're about to die because they've just fallen off a virtual cliff?

Consider also the Illusory Consensus Effect: mere repetition of information increases the estimates of group members that other group members believe or already know that information. Logically redundant, rhetorically effective.

We're apes with a souped up prefrontal cortex - critical thinking is expensive so applied selectively (see Tversky and Kahneman, System 1 vs System 2 thinking).

Now I know that even without engagement-maximizing algorithms or anonymity, most content on the Internet is still from self-selecting outliers. You don't walk down the street and listen to whoever shouts at you the loudest to gauge public opinion, so why care about Internet commenters (including me or you) when statistically normal people are "lurkers" who read and move on?

> Why do we all (and I include myself) so easily and often forget this simple truth, and fall into the trap of believing the world population consists mostly of the ignorant and malicious people that haunt public comment sections?

Because we've had millions of years to evolve our social instincts, and not even a single generation to adapt to the current state of public comment sections? In real life, where there aren't the same sampling biases, it makes perfect sense to believe the perspectives that are repeated by peers (as honest indicators of public opinion, if not at face value).

Also because there are major profit incentives for social media companies to make people think they're important fora for public discourse.

I think for-profit social media should probably be viewed as adversarial attackers. Their incentives are not aligned with what we need for healthy relationships and discussions. But even if you remove the profit incentive, it's still a new environment that we lack natural immunity to.

The problem with being nitpicky is that fixating on isolated/arbitrary details often just means missing the bigger picture in a way that's even more incorrect. Good for "gotchas", but not intellectually productive.