Kudos to the OP for posting his opinion. That has nothing to do whether he is right or wrong, since it is only his opinion. Flaming a guy for posting an opinion is juvenile. I say let people have whatever opinion they want to have, whether it matches anyone else's or not. I can say that I would never want to live in a world where everyone has the same opinion as everyone else. That would be way too boring. If you think classic rock is great and contemporary music bites wangus, then cool. And if you think contemporary music is da bomb and classic rock swallows, then cool. Go forth and enjoy what you like, and don't flame people for having an opinion that differs from yours.
As for me, I happen to share a similar opinion as the OP. For example, whenever my wife and I are cruising around town and we flip the radio channel and Nickelback happens to be on, we bust out laughing because the singer always sounds like he is sitting on the toilet trying to push one out after four days of constipation. But hey, that's just our opinion.
I will say this: there was alot of really crappy music made back in the 70's too, most of which I have spent decades trying to erase from memory (Iron Butterfly, Foghat, Mott the Hoople, etc). But in my opinion, there was a higher percentage of good music being made back then as compared to today (Led Zeppelin, Yes, Rush, Eagles, Chicago, Elton John, James Taylor, etc.). I would say 60% good, and 40% crappola in the 70's. Whereas today it's around 10% good and 90% tripe. Again, just my opinion. It seemed easier to find good music back then. Today you have to look much harder to find it because we are constantly bombarded with painfully boring power chords and cookie monster vocals.
All IMO of course.