I strongly disagree. Just because compression is common in pop music (and perhaps overused in some genres) doesn't mean new music isn't innovative and dynamic. When I listen to music say from 1920 to 1950, it is so often so incredibly lame (not always). It's basic ideas and chord progressions and simple melodies with lyrics that don't say much.
Music is a way for people to express themselves and relate about how they see the world. People didn't stop doing that recently. In fact, I'd say people have been emboldened to say even more and push what music really means.
That could be true - but this was specifically referring to the volume levels in recorded music, rather than variability in melody or composition.
It's not just compression. Rick Beato has talked about this a lot.
Popular music no longer has any key changes:
From 1960 to 1995, between 20% and 35% of Billboard Hot 100 number one hits in any given year contained a key change. Around the turn of the millennium that rate started to dip until it hit 0% by the end of the 2000s. [1]
I believe that simple 4/4 time has also become more prevalent as compared to more complex time signatures. I don't have as good support for this claim, but the AI tells me "4/4 (simple quadruple) has dominated Western popular music since at least the 1960s, and corpus work suggests that compound and non‑4/4 meters have become less common over time in mainstream styles, implying an even higher proportion of songs in simple 4/4 today.".
Beato is also fond of pointing out how modern music is written by committee, and that modern artists are more a "product" than ever before. From memory, he's pointing out that in the past, the credited writer of popular songs was usually a band, or perhaps a single person. But more recently, the credited writer is a list of multiple people not the band (and in fact, top songs across recent years have been notable not under the name of a band, but of an individual performer).
EDIT: Further querying leads to this as well:
Timbral Variety: The "texture" of sounds. In the 70s, you had a mix of acoustic, electric, and orchestral layers. Studies show a "homogenization of the timbral palette" since the 1960s peak.
Lyrical Complexity: The vocabulary and reading level of lyrics. Analysis of Billboard hits shows the average reading level has dropped from 3.5 to 2.7 (roughly 3rd grade) since 2005.
[1] https://www.cantgetmuchhigher.com/p/revisiting-the-death-of-...