https://pudding.cool/2017/05/song-repetition/This article does a statistical analysis of popular music over the past few decades and demonstrates that popular music has consistently been getting more and more repetitive. I know that repetitiveness is not synonymous with quality, and that some songs use repetition very effectively and a random jumble of notes would be low-quality even through it would be non-repetitive. But there is generally a correlation because complexity and quality of music, so it is safe to say that modern music is getting worse.