This shouldn't be downvoted; it is certainly a thought-provoking assertion, and seems true to me at the first impression. Many new words come out of slang from young people, who are much less likely to have "professional" level grasp of language that someone with a lot of higher education will have; the second kind will be more like to lean on existing words from obscure sources they read.
The last Oxford Word of the Year was "goblin word", which does sound like it comes from young people, who likely don't have expert grasp on existing language. The full list[1] does contain words like "youthquake", "post-truth", "climate emergency", "squeezed middle" which are likely to have been coined by a much older crowd with more higher education. The second kind of phrases feel much less new, even though both these and "goblin mode" are made up of existing words.
Conclusion: claim seems correct but more research needed.
People making new words sometimes don't have a command of existing words that are not out of the ordinary, wielded by plenty of folks with just a high school diploma.
Now "post-truth", "climate emergency" and "squeezed middle" are hardly new words. The first one is just applying the highly productive prefix "post". Anyone with a decent command of English can do this. E.g. Rust programmers are envisioning a "post-C" tech landscape. "Climate emergency" is just an obvious word combination: there is an emergency and it has to do with climate. Someone in 1920 could have pointed to the new Coca-Cola bottle and remarked on its squeezed middle.
In the case of shenanigans, I don't suspect that the person who coined it didn't know of ways to express the idea.
Shenanigans is one of the words which expresses, "things are going on that don't sit well with me/someone for some reason", which is a variation on "I don't like it".
People are attracted to new words in this area, because it isn't interesting or original to make remarks about not liking something. A fresh word adds color to it.
> Words are made mostly by people who have poor command of existing words.
I think they are optimizing for the culture (which includes new technologies and methodologies), which shows competent command. These new words are memes in the most useful sense and they do not limit themselves to other cultures' (even past versions of their own) vocabulary.
Some people may imagine this degenerates into a condensed "newspeak". The defacto human behavior is to generate utilitarian permutations, so this is unlikely to occur or be maintained organically.
