In a way, that would just be a return to before the second industrial revolution, when popular music and consumer products were more more regionalised. "Everyone in the world, or even the country listens to the same thing and drinks the same cola" is a recent phenomenon, and arguably not that valuable a phenomenon.

In practice, though, I'm sure there's quite a bit of sharing musical tastes between friend and interest groups; it wouldn't be literally everyone listening to different things.

I would wonder does increasing consumer choice ultimately erode generational identity a bit, though. So much of the "what is a boomer/gen X/millenial" is founded in what popular culture everyone was consuming in a given decade.