People with good STEM education, even with PhDs in that field aren’t necessarily competent voters and good decision makers outside of area of their interests. Understanding economic policies is still an effort that many aren’t willing to take.
Personally I suspect there's a floor (can read a chart, understands growth rates and compounding in general) which the public need to assess arguments constructed by specialists, while the rest is mostly understanding ideology.
The reason I believe that is, I think I can pretty much predict 100% of the conclusion of most articles written for the public by knowing the names & affiliations of the authors and the topic. The only uncertainty is what sources and statistics they will pick to reach the conclusion required by their ideology.
Where do you get that information from? According to the CIA, it's 100% (https://www.cia.gov/the-world-factbook/about/archives/2023/f...). North Korea Info (https://www.northkoreainfo.com/why-does-north-korea-have-a-h...) gives a slightly lower estimate of 97%-99%.