When looking at the popularity bar (thumbs up symbol) next to a song, I think it'd make more sense to have it be normalized to show which songs are most popular within the album or playlist you're looking at. It doesn't really provide useful information to see that every song in an album has 3 bars of popularity. Especially when new music comes out, it creates a way of voting which songs are best.
iTunes used to do this based on which songs were most purchased, and I thought it was helpful and interesting.
Updated on 2020-01-18
Marked as new idea.