This is just my opinion so take it for what it's worth To me if the music has no melody then in the case of most modern rock it's just white noise @ 110% modulation. Even Ozzy made a few tunes that actually sounded musical compared to most of what is out there. The advent of MTV and the videos was the last nail in the coffin of R & R as I knew it. When you replace talent with good video work then you end up with something that's eye catching and pleasing to someone with an attention span of 15 seconds or less. I used to watch MTV when they had the Best band" type shows for a while. It always came down to a bunch of young twits who weren't even alive describing what Led Zep and others were all about. I always thought if those guys were so wise their bands would still be working putting out that punk schlock or whatever it was they did. I'm just another old Geezer who is tired of some tattoed, pierced punk telling me why Waters & Gilmour couldn't get along.