[Meta?] There’s more to pop culture than music

That's the thing though; there are many TV shows that don't show the change in cultural zeitgeists or actually reflect the era in which they were produced in. I do agree with you that there are certain TV shows which can be more representative, but as a source for looking back on the trends of past eras, music is going to be far more reliable as a whole.

With music, it doesn't matter if a song is a popular hit or not, every single song released is a product of its time, and the song is going to reflect the attitudes, thought processes, and preferences for certain aesthetics/styles that went into making the song at the time of its conception. I would argue that music is the more reliable representation of change as a whole since there is a context behind the release of every song. Television is too fluid as a medium for it to be truly representative. With television, you can obviously use both sound and visuals to depict something as you wish, but that's inevitably going to lend itself to the possibility of greater inaccuracies. I mean, look at that Season 8 episode of Game of Thrones where a coffee cup was seen on a table. A polystyrene cup in a series which is supposed to be set in medieval times? The final two seasons of Malcolm in the Middle from 2005/2006 show frosted tips and feature Y2K-era pop-punk songs as backing tracks, but the overall zeitgeist of the time had shifted away from Y2K/early 2000s culture and the transition from pop-punk to emo was already well underway. It isn't an entirely accurate reflection of the pop culture of both 2005 and 2006, nor is it reflective of the change over time for the reasons I mentioned in the previous sentence.

I just feel that in the case of music, what you hear/see is exactly what you get. You're not going to spot The Beach Boy's "God Only Knows" on the charts in 2021 as there would be no reason for it to be on them. The band has been irrelevant in the mainstream for over three decades and that style of pop-rock died out when the cultural '60s did. People's tastes in music are naturally going to be different from what they were like when the song was released 55 years ago. "Bohemian Rhapsody" only saw a resurgence in 2019 because the song had become a by-product of the recent breakthrough in popularity of biopics. If you compare the music charts from 1982 to 1987, for example, you're going to see the change in peoples preferences for certain styles and the further evolution of music genres. Even outside of the mainstream, more niche genres like "maths rock" and "vapourwave" came to be because the evolution of technology over time allowed them to develop into what they are. They're a reflection of where society was/is at from a technological and stylistic point of view.