"The masses always focus on the Now, especially younger folks. Elvis fans didn't listen to Frank. For Beatles fans, Elvis was the prior decade. When I was a kid, Paul was backed by Wings, George was past his prime, John was retired, and Ringo's peak was over and dead. I became a Beatles fan, but if there were 5 Beatles fans at the time in my entire high school class it would shock the shit out of me. I can remember getting a single "Cool!" comment when wearing my Beatles shirt, though plenty for wearing a Stones shirt since they were still releasing albums."
I largely agree with what you said, even though I think Jerry has a couple of decent points, in that as part of the last generation that grew into teenagerdom without the Internet being ubiquitous (late 20's/early 30's), there are older references that I get that people just a few years younger don't get and when I ask them, they've never heard of the book/movie/TV show. But, again, maybe I'm getting old too.
However, I actually think it's easier for kids to get into older music these days. Youtube/Spotify/etcerera plus songs being three minutes (as opposed to 30 minute TV shows or 120 minute movies) mean it's easier for a kid to click on a link for an older band and as a result, get into other stuff. On a purely ancedotal level, I see a lot more kids in 'older' band t-shirts than I ever saw at my high school.
Now, I'm in Seattle, so it might be different in Des Moines or Peoria, and I'm well aware most kids just listen to the latest hot thing of the moment, but I do think music is the one thing that the Internet has helped widen access too, at least among older stuff. It's one click away instead of having to dig through your Dad's old records or be at some creepy record shop.