You know how sometimes there's that hit song (or artist) that's super popular but you just don't like it? Sometimes it's because it's ubiquitous to the point you begin to resent it, but sometimes it's actually because the song isn't really that good. Those songs will be considered classics in a couple decades though, and there probably won't be too much push back on that from people who were around when it first came out. Some of my uncles used to be DJs, and they've put me onto old bands I'd never heard of before, but by all accounts the music they think was the best was popular back then too.
I'm sure we can all name examples of current music hits/acts that probably will perhaps undeservedly achieve that classic status in the future, but what about past music? Personally, I'm all about the deep cuts, and sometimes I wonder if I would have liked some of the bigger acts if I came up during those eras. For example, no matter how I try I can't really get into the Beatles, but I'm not sure how much of that is taste and how much is just being from a subsequent era that had already absorbed all the changes they made to pop music.
Of course, radio was a lot more important in the old days, and people having a lot less access to their own choice of music back then as compared to now would have shaped their tastes, but let's try to leave that aside.
Edit: I'm not just talking about rock music, btw. If you think Chopin is overrated, by all means, make your case.