Goth seems to be this freefloating set of genes (sonic and in terms of the look), it pops up all over -- in quite mainstream metal like Avenged Sevenfold who have a touch of the Alien Sex Fiends and Specimens (ie campy rocky horror end of goth) to AFI who named their fan club The Despair Faction and covered “Hanging Garden” by the Cure.... the black metal seem to owe a lot to things like cocteaus, dead can dance, the more atmospheric/ambient end of goth and industrial
on blissblog i said something about Xasthur sounding like Robin Guthrie jamming aimlessly with all his FX pedals on full
on the things that connects it all is whiteness i think -- industrial, goth, gabber, power noise, the post-Slayer kind of metal (when the blues roots have completely been eradicated) etc -- it is all music that has no relationship with black music at all. not intrinsically a bad thing except that then you do get your Nordic pagan sorts do their own highly dubious versions of all of these genres...
one of the things about "militant dysphoria" / misanthropy is that when it gets politically mobilised it can lend itself to the right wing as much as the left wing... check out this on "martial industrial" -- scary!
perhaps "blackness" in music is connected to vitalism, somehow