In other words, what apparent imperfections in human reasoning
A) Remain apparent after the Replication Crisis,
B) Aren’t secretly adaptive/reasonable in some counterintuitive way, and
C) Deal most damage to the people they inhabit (and/or those close to them, and/or wider society)?
Conjunction Fallacy. Adding detail make ideas feel more realistic, and strictly less likely to be true.
Virtues for communication and thought can be diametrically opposed.
The fundamental attribution error is another important one. I sometimes find myself slipping into it myself when I get tired or inattentive, but for most people I observe it seems fully baked into their characters.
The Typical Mind Fallacy is the most important bias in human reasoning.
How do I know? Because it’s the one I struggle with the most!