Those Top 40 singles were spoon-fed to you by Clear Channel within a very limited selection from the Top 5 major record labels.
That doesn’t change the shared cultural experience. Decades had “sounds”, disco was a thing in the 70s because everyone heard it. Today there’s no shared cultural zeitgeist. You might find communities on reddit etc, but they aren’t local.
Those Top 40 singles were spoon-fed to you by Clear Channel within a very limited selection from the Top 5 major record labels.