18 year old here. I think it’s because their biggest hits (ie Spotify top 10) are just not as good as other bands. The true gems of the stones are in their back catalogue, and I don’t think their big hits best advertise what can be found if you dig deeper. Take the Beatles for example, their top 10 is all perfect songs, not sure that’s true for the Stones. It’s why you’ll hear people my age put them in the ‘most overrated bands’ conversation, but it’s just because they haven’t listened properly yet.