It’s been argued before that this is the only reason that DK gained any notoriety; because it feels right, not because it is right. It’s the “just-world” theory: we want to believe that confident people are overcompensating.
Is it actually intuitive though? Consider your own example. Most people who don’t know piano or figure skating are well aware that they don’t know, and do not rate themselves highly at all. Would it be surprising to learn that people who don’t know any law or engineering don’t often hold any doubts about their lack of skill, and by and large are not deluded nor erroneously believe they’re great at these things they don’t know?
The DK paper didn’t measure knowledge-based skills like piano, figure skating, or law. It measured things like the ability to get a joke, and conversational grammar. How would you rate your own ability to get a joke? (Does this question really even make a lot of sense?)
It’s important that the methods in the DK paper focused on tasks that are hard to self-evaluate, because when people have tried to replicate DK with more well defined knowledge-based activities, they have often demonstrated the complete opposite effect, that there is widespread impostor syndrome, and skilled people underestimate themselves.