Speaking as a life-long musician, I never understood the appeal of the chugga-chugga death metal cookie monster vocals thing. My guitar playing 22 year old nephew loves it. Real rock music is melodic and has a structure, preferably with real singers.
We need more like Van Halen, ZZ Top, The Guess Who, The Grass Roots, and solo artists like Jimi Hendrix and Janis Joplin. All these have transcended their industry-imposed genres and are timeless.
Add Hall & Oates to the list and you have crossed several genre lines from R&B/Soul to Hard Rock to Bubblegum Pop. Those guys were/are amazing in their scope.
I can't agree with this more. Although I can't listen to The Grass Roots without thinking of Creed from The Office.
Over time, more and more labels have been put on music to further subdivide styles, types, genres, etc. Mainstream anything doesn't really exist anymore.