Earlier quoted context omitted.
I have literally have people tell me that this is still rationality because it's the rational thing "for them". Like, the weirdest one was a cognitive psychology doctoral student. I mean, okay, if you can redefine rationality to be completely subjective, then sure, rationality is flargikriggendurf.
In addition to the other fine replies, let me point out that "humans are irrational" is the negation of a very small point. It allows us to think we know something, when in fact what that statement tells us is only that we don't know something about human behavior. It is logically much like saying "Humans are not 7-year-old bulldogs named Fido living in New Jersey on the second floor of a shared house." It's a true s…
Admittedly, this is because "homo economicus" is sophomoric in the first place: it proposes an actor who has no computational or informational bounds and sees the world only in terms of a single real-valued variable called "utility", which is generally constrained only to be any monotonic, continuous function of their monetary net worth. This actor then optimizes expected utility with no regards to modeling causal structure or to which observables are actually ergodic.
No such creature ever has, or in fact ever can, exist in the real world. In limited domains where ergodicity holds, computational needs are few, and small sample sizes can yield very good inferences, we can do thought experiments about what such a creature would do, and act according to those if we please. But holding that such behavior is the normatively correct way to act when it's actually impossible is the kind of religious thinking one gets when composing "normative theories" without experimental basis.