Later Emperor certainly has plenty to do with black metal philosophically, and they also utilise plenty of stylistic traits from more traditional black metal too. I can't comment on Dimmu/COF, since I'm not at all familiar with their later material.
Would Funeral Mist count as slick? Maranatha has a very clear production overall.
Dimmu, CoF and later Emperor isn't black metal, so they're invalid from the argument. Stylistically, and philosophically they have nothing to do with the genre, and the tag remains only for the ease of use tag for mainstream magazines.
Disagreed. CoF started out as a satanic themed band, with Danni Minogue claiming to be a satanist. Dimmu espoused satanic and anti-christian values, and the last Emperor album was about prometheus and the discipline of satanism, Ishahn to this day being a self-proclaimed satanist.
Black Metal was about satanism wasn't it? Sure, these bands have changed and become hugely commercial, or may even have started off commercial, but perhaps it was all part of the great evil plan? So that hordes of yet-more-evil folk rise up in rebellion against it and further the cause.
*nods and says "ahh..." wisely, like Jesus in the Richard not Judy sketches*
Dimmu Borgir have never known what they were talking about. I recall a Terrorizer interview around 2000ish when Shagrath even admitted his lyrics weren't actually about anything.
CoF have only ever flirted with satanic imagery, I can't say I've paid them a great deal of attention but from what I remember their songs are generally about vampires and Ann Rice styled gothic romance aren't they?
Emperor may have the philosophical side down, but there's nothing "black metal" in my eyes about at least their last two albums.
I think that view on black metal is just another one of Euronymous's misguided, ill thought out ideas.