Starise, maybe you answered this question with the condition "popular music"? Since we know pop music is getting more homogenized and generic, it does seem consistent that the classic band format would be just as rinse and repeat as the rest of it.
I asked questions, years ago, why does popular music insist on drums and bass supporting guitars and singers? Why do we have guitar solos, but not drum solos and bass solos? Why is it that the guitarist is the only one that is invited and somewhat expected to be the "virtuoso" of the band, while drummers and bassists are to stay out of the way and be quietly amazing without anyone noticing except other drummers and bassists? Why is it laudable to be awesome at staying out of the way and not really being noticed?
I decided that answer was because 'popular'. Popular = commercial, hyper production, fast food music. Popular is to music what McDonald's is to cheeseburgers. Pop music sounds to me like a stripped down joke of corporate sales psychology. It's what car salesmen would do if you asked them to listen to good music and create a popular version for high sales numbers.
And, yes, it hurts my soul that the Beatles were pop rock. Something changed between then and now...or maybe it was always a hyper commercialized art form, and it has simply evolved. I don't know. But pop just turns my stomach anymore. Give me metal...progressive metal baby!