Black Sabbath made it clear their concept was to make musical horror, and to defecate on the hippies who were telling us that all we needed was love (shorthand for "socialization, altruism and polite tolerance of anything").
The kids growing up in the 1980s, born out of the chaotic period that birthed metal, grew up in an entirely permissive world created by those attitudes, although people tried to hold on to "practical" concerns. Your parents couldn't tell you to not take drugs, drink, or have sex because... they did these things. In spades.
The 1990-peaking generation, therefore, were hellbent on destruction -- either of themselves, or of the illusions that made the world they grew up in. Much like kids rebelled against the stodgy 1950s and post-war pretense of America and Europe, kids rebelled against the stodgy hippie bullshit they suffered under through lack of guidance, no social order, and so on.
Kids in the 2000-peaking generation were born in the early 1980s and the Reagan period, and so they have nothing to rebel against but the counterreaction, and are completely lost when it comes to understanding this music -- with a few notable exceptions who realize its outrage, like that of the Romantics, is against a calcified order of appearance and not reality, and their conduit to reality is nature/deep introspection (not individualism).
I find this interesting. Maybe you will.