Comment by Jongseong

You've got the gist, but North Korea does use tonnes of Sino-Korean words, which are like words of Greek and Latin origin in English. You can't simply eliminate such words from the language altogether. What you can do is to favour pure Korean words over Sino-Korean when coining new terms or standardizing terms for technical usage. So North Korea might use a bit less Sino-Korean than the South (I'm not even sure though, because there are other factors such as loanwords in South Korea displacing Sino-Korean words there). But this makes barely a blip on the language as a whole since so many basic words in Korean are Sino-Korean. Even most North Korean terms you're ever likely to hear are Sino-Korean: Juche, Son'gun, Chollima, Rodong missiles...