That is a great analogy with the German experience. This is what the article is about.
This is what I'm talking about:
Wikipedia says its possible to count the number of entries in a dictionary, but its not possible to count the number of words in a language:
Language Words in the Dictionary
Korean 1,100,373
Japanese 500,000
Italian 260,000
English 171,476
Russian 150,000
Spanish 93,000
Chinese 85,568
https://blog.ititranslates.com/which-language-is-richest-in-words
Obviously, there are methodology problems about which language is richest, who has the most words, what qualifies as a separate word to be counted etc.
The South Korean language is exploding with new vocabulary every day. Some newly coined unique and unprecedented words or usages appear for a short period or only a day or two and disappear and others go on, as long as a particular social, political, technological or media situation continues. The result is thousands of new words every year. You don't have sleep for a decade to get behind, native speakers often don't know what people on Korean tv news programs, or talk shows mean when they are speaking in the principal Seoul dialect. I know it's a thing particularly with programs devoted to younger audiences to make up or use such words because it's trendy or a fad.
To assist the viewers the broadcasters post quotes on screen or subtitles so the viewer can get the main idea. Commonly, when this occurs the key words won't appear in a dictionary, whether formal or contemporary, because someone just made it up. It isn't just a class problem or one of regional dialects, the educated classes, journalists and media are among the biggest offenders.