Diction, grammar, syntax, rhetorical tools - it seems progressive, state-run education has got rid of them all.
When helping my parents clear out my deceased grandfather’s house years ago, I came across a high school textbook he used - entitled something like “Logic and Rhetoric.”
Being a public school educated Gen X, it was like reading an abstruse religious text for the first time. It covered public speaking and writing, logical fallacies, and rhetorical devices - chiasmus, anaphora/epistophre, tricolon, etc.. And they learned this in High School!
Educated people of 100+ years ago would have, as you say, modeled themselves on accepted models (often ancient Greeks and Romans, Shakespeare, etc...) - and would have easily recognized the rhetorical tools used by great speakers like Churchill or MLK.
Now we have no clue.
Yes, it’s truly sad to see to downward spiral in motion.
The habit of dropping consonants is nauseating. “I di-nt say that.”