I felt I should clarify before I left this here, that black metal points to something specific mainly in its pointing to a specific period of time and specific bands and the attitudes shared by them. It is unfair to try to abstract it and say your abstract omits the founders; the founders ARE what it is. This is because they never got together and agreed on some kind of "this is what black metal is". Rather, when we try to think of what black metal is, we think about what all those bands shared. Again, the terms are meaningless, we look to evidence to see what it really was.
It's just not that easy. What I am saying is something far deeper than just the Black Metal scene and it's forefathers, I'm asking about Black it's self, what is black in this case? A philosophy of mere nihilism? why is it called black then?
I think looking at the things the founders and also what black metallers of today share in common is a great source of evidence. However, the problem is that we can't even agree on the evidence. We can't even agree on who the founders really are, and what they had in common. The roots of black metal may extend very far back in time, beyond classical times, into prehistoric shamanism with forms of demonic worship and ritual chanting, and possibly even before physical existence! So who are the founders of it all?
Regardless of any of that, whoever the founders are really doesn't mean anything to us at all anyway. All of these so called founders all shared the fact that they were human in common, and like the rest of us, all had their stupid vices. Quorthon bragged in interviews about how he fucked women in air planes and limousines, and he was drunk when he recorded "The Return", yet when I listen to that album I don't even think about Quorthon. It wouldn't have mattered to me whether "The Return" had come out in 1970 or 1999, dark music touches my aesthetic existence on a deep level, and is therefore timeless. When that is achieved, it does not need a foundation or founders, because it supports it's self.
When most people listen to black metal, they do not think of the black metal scene, because black metal music is not aesthetically scene based (unless those are your aesthetics). I think most of us would agree that Black metal is against the mundane aesthetics of things like "scene", if we agree on that, we are making very good progress.
If you still want to stick to the founders argument, there is nothing illogical about it, as long as make up a new name for the genre you call black metal. Take those bands and call them all "Leroy's interpretation of what the founders of black metal thought - Black Metal" It's much more logical to do it that way.
What I am saying is, we should not use the same terms if we do not agree on them. If we continue to do so, things will remain as they are, as a group we are confused. This is why COF and Dimmu are black metal now. Philosophically, it wouldn't be incorrect for certain deathgrind bands to be black metal either.