What happened to the days of where somethings did not rhyme but was plugged with another word? Like Johnny Cash, Journey, Frank Sinatra, Dean Martin and others. Even if they did it it doesn’t sound so blatent. Did Mozart and Behtoven do it back then?
I think what you’ll find is that a) you’re selecting a very limited sample of music from the 40s - 80s (hint: most music of each generation is rubbish and formulaic), and b) you’re selecting a very limited sample of modern music, likely from a single source.
Aside from what others are saying, you’re also suffering from selection bias.
Of course, on top of that, each generation has a new musical technology that revolutionizes the sound, with the downside that everyone using that technology sounds pretty similar.
These days we’ve got digital studios that can not only auto tune the instruments and vocals, but also ensure the audio sticks precisely to tempo and time signature.
You’ll see a similar thing shortly after the advent of the organ and harpsichord, where musicians suddenly had precise control over when a tone started and stopped, and a musical notation to represent that timing; suddenly a lot of music featured formulaic 16th staccato runs, because it was now possible for an entire group of musicians to do so relatively easily.
So… look for recent music that starts with a poem and then sets it to music; there’s lots out there; you’re just unlikely to have it recommended to you on Spotify unless you’re already listening to similar music.