The article is correct. The effect is statistical not psychological. It emerges even from artificial data and occurs independently of the supposed psychological justifications even for data where those justifications are clearly removed.
If you adjust the experiment design to avoid introducing the auto-correlation you get data that doesn't show the DK effect at all. Some might take issue with the adjusted experiment as using seniority related categories like "sophomore" and "junior" as skill levels has its own issues. To show the DK effect is real you need to come up with a better adjusted experiment that avoids the autocorrelation while still generating data that generates the effect. It's unclear if that's possible.
If you adjust the experiment design to avoid introducing the auto-correlation you get data that doesn't show the DK effect at all. Some might take issue with the adjusted experiment as using seniority related categories like "sophomore" and "junior" as skill levels has its own issues. To show the DK effect is real you need to come up with a better adjusted experiment that avoids the autocorrelation while still generating data that generates the effect. It's unclear if that's possible.