It's reductive to suggest that the top 100 represents "general culture" (whatever that ambiguous term means). There aren't solely niche musicians outside of the top 100. Theres plenty of musicians with millions of listens/views on streaming media that don't enter billboard lists that have extremely prodigious careers that have complex lyrics, use a wide assortment of instruments/equipments, evolve genres, etc.

Your data might be objective, but it's still a narrow slice of a much broader ecosystem.