The point of this story is to illustrate that the Dunning-Kruger effect has nothing to do with human psychology. It is a statistical artifact — an example of autocorrelation hiding in plain sight.
What’s interesting is how long it took for researchers to realize the flaw in Dunning and Kruger’s analysis. Dunning and Kruger published their results in 1999. But it took until 2016 for the mistake to be fully understood. To my knowledge, Edward Nuhfer and colleagues were the first to exhaustively debunk the Dunning-Kruger effect. (See their joint papers in 2016 and 2017.) In 2020, Gilles Gignac and Marcin Zajenkowski published a similar critique.The Dunning-Kruger Effect is Autocorrelation – Economics from the Top Down