• the whole "metal=classical" is a big practical joke, and YOU are the punchline
In order to understand the connection between metal and classical, it's necessary to notice that, certainly, metal is a form of popular music, with a rock background. It's foolish to think that after Wagner there was Metal, no. Nonetheless...
There was popular music dominating the entire scene, right? Yes, goofy themes and boring structures. Some people just got enough of that in a few years (Black Sabbath, Robert Fripp, Jethro Tull) and so they took the rock band and its characteristic syncopation, yes, to bring different themes and structures, which couldn't be linked to anything, not even jazz, as would to classical in melody (a focus on diatonic modal scales, not just pentaphony) and in narrative structure. Not only metal music, but also bands like Kraftwerk and Dead Can Dance, joined into this classical orientation.
From popular music, neoclassical music merges granting it a... higher direction.
Neoclassical music preserves ancient tradition and accelerates it into modern form, using the values that are eternal to guide us from the past into the future. Neoclassical popular music includes some artists from the following genres: ambient, electronica, synthpop, black/death metal, noise, industrial, EBM and postpunk.