There's certainly nothing wrong with modern music, bands now are as good as they've ever been.
Its the dinosaurs who listen to Planet Rock who just won't listen to bands they don't know. Its their loss, there's a whole heap of new music they'd probably love if they were more open minded.
Discovering new bands is something I love, finding they have a couple albums for me to check out and enjoy and hear new, good stuff. I love Sabbath, they've probably influenced every band I love but Id probably only put one of their songs in my top 10.