True and agreed.
Eehhhh....
Not so much. Hendrix, Beatles, U2 will be listened to forever so long as society doesnt collapse. Tell that to Loverboy, Styx and Foghat. Or even a lower tier, Night Ranger. The 70s #1 lists for both singles and albums is littered with craaaaaaaap. Forgettable crap that only endures on the Oldies station, which btw, is starting to play Prince. Only a matter of time before all that "great" music from the 70s is utterly forgotten. A mere 30+ years ago.
Thats just the 80s. The 90s arent old enough yet to determine who will and wont be forgotten. But forgotten it shall be to some degree.
My old man hat says a lot of new music is forgettable. Time will tell.