Death metal is more twisted and abstract in design, kind of like decoding information of what happened rather than feeling it emotionally. Yet stylistically, doom borrows more from the subterranean, gutteral sound of death metal.
I really like this observation.
Death metal was born in the mid-1980s when the Cold War was raging, and people were trying to decode paranoia and politics and figure out what they wanted.
Black metal was born after the Cold War ended, basically picking up history after the conditions of the end of WWII, and represented people trying to figure out why the nightmare continued.
Bill Clinton on TV was scarier than Reagan. Reagan had a goal; Clinton pandered to the lost and clueless, the self-victimizing and discontent. There was no longer hope for normal, healthy people trying to have productive lives; society went from war to 100% focus on the pitied in only a few years.
Black metal pointed out why this failed and immersed us in an atmosphere of the ancient, and the feral future. The next 1000 years are ours.