pocketcheese

I actually did something similar! I wrote a small blog post about it here https://www.popnalysis.com/blog/lyrics-over-time/

But I came to the same conclusion as the op comment. Music can't really be judged by any one metric! But that doesn't mean that you don't gain insight into how music has evolved!

also, I did release my entire lyrics dataset that I scraped (about 500k) for free.