The vocabulary problem is caused by our educational system, which is common throughout the world. Its because kids are grouped with their own age group and the only person talking to them with a bigger vocabulary is the teacher, and teachers are usually trying to dumb down their vocabulary so kids can learn the material faster. I used to be a teacher. The solution is multi-grade level classes, maybe even putting kids in the same classes as adults. No kid should ever be sitting next to someone of the same age.
Discussion
How was schooling organized in, say, the 50s? (Not referring to segregation). Private schooling still produces people who can speak eloquently. I think it's a case of training (propagandizing) teachers who then in turn teach that to kids. 20 years ago I wouldn't take much issue with putting my kids in the school system, even knowing what I know now. But today? No way.
Does pop music play no role in this? TV and entertainment? Seeing as that influences people of many age groups, it feels like that would be a bigger driving factor.
Everything plays a role. Pop music certainly does, but phones are worse. That was one of the things that disappointed me while I was trying to shift to teaching in the US - teachers are mostly not allowed to take away phones, and the exceptions are only after state-level legislature that prescribes when and how they can take away phones. Teachers in the US really have their hands tied, and any slight deviation (in one direction) equals prompt dismissal.
The 1950's, I think, was different in that there was a kind of momentum from previous generations still affecting them. Our society was just beginning to be litigious and heavy with policy. A lot of schools still taught marksmanship, with real guns. People in general were tougher and more responsible. But if you go back to before ww2, classes were mixed ages and several grades were together in one classroom. Modern school structure is modeled after British schooling, mostly invented at Cambridge, and it was pushed in the US by Roosevelt and all his socialist bullshit. IMO, Roosevelt murdered America, and only a few people are able to see it now because the detrimental affects of policy unfold over generations.
They only teach the Trivium in the elite schools now. There is a reason people are getting dumber. 
We should bring that back, for sure. I'd be worried we'd botch it, though, by making the class book-heavy. If I did it, I'd try to blend rhetoric with drama, make the kids compete in oratory performance, and sprinkle in the classical education between performances.
They need to scrap government schools and compulsory schooling and things would quickly fix itself. Education and learning is a life long journey and there is no need for kids or adults to spend so long "learning"
100%
I am strongly in favor of apprenticeship for poorer families and private tutoring for wealthy families
(the main methods of instructing children & young adults for all of Western history)
Government Schools are a jobs project scam.
I said the same once to another teacher, and he couldn't process it. It just couldn't penetrate... I said if a kid doesn't want to be there, he should be able to go. If a kid wants to work, they should be able to work. That way, they'd realize what an opportunity school is, or can be, and then they'd grow up and some would be teachers, and they would teach like it actually matters. Because it does matter, and they think think it matters, but they don't **_know_** it matters, because if they did, they wouldn't let class be a waste of everyone's time.
💯> if they don't have the choice to be there, it is a prison.
I have found kids interest and curiosity alone will inspire them to learn, if you try to force them, you will kill any interest they might have had.
That right there is the Dao of teaching. Can a teacher cause kids to be interested? If yes, then that's a good teacher, and it doesn't matter if they have experience or assign homework or anything that normally qualifies you to teach. A lazy teacher can be the best at it, if they can pose the questions that cause the student to pursue it independently.