Rock is not dead, it's just not dominating the charts like it used to and people like to use that to support the idea that rock is dead. The rock and metal genres are alive and well, you just have to dig a little deeper to find quality music.
I understand the appeal of buying a CD or Vinyl record but on the other side of the coin, why would I spend $12 on an album when I can pay roughly the same amount monthly to have the same album and millions of songs that I can listen to anywhere? Hell you can even find the songs for free on YouTube most of the time. If you want to support your favorite artists, buy some merch. They make a lot more money off of merch than album sales these days.