The seemingly obvious solution would be to try to reach those people through political ads, expert opinions, and logical arguments that educate with facts. Except none of those things seem to be swaying any Trump supporters from his side, despite great efforts to deliver this information to them directly.
The Dunning-Kruger effect explains that the problem isn’t just that they are misinformed; it’s that they are completely unaware that they are misinformed. This creates a double burden.
Studies have shown that people who lack expertise in some area of knowledge often have a cognitive bias that prevents them from realizing that they lack expertise. As psychologist David Dunning puts it in an op-ed for Politico, “The knowledge and intelligence that are required to be good at a task are often the same qualities needed to recognize that one is not good at that task — and if one lacks such knowledge and intelligence, one remains ignorant that one is not good at the task. This includes political judgment.” Essentially, they’re not smart enough to realize they’re dumb.