<i>For example, the OP itself talked about &quot;folk metal&quot;, a sub-genre that uses traditional themes, musical styles, and instruments</i><p>Folk metal is actually well inside the tradition of heavy metal, that spans from the black&#x2F; gothic to the epic and fantasy themes. By the way there&#x27;s even a more extreme musical genre called &quot;folk&quot;: where people from different regions of the world perform <i>actual</i> folk songs strongly connected with their real traditions. Can you imagine, you can actually listen to folk music <i>outside</i> of the rules of heavy metal? That&#x27;s <i>extreme</i>.<p><i>Metal fans love to bicker and debate ... over whether ... still counts as metal at all.</i><p>Exactly. A little bit of evolution or variation and people start debating whether you&#x27;re still in the group or out. That&#x27;s silly.<p>And oh yes, I&#x27;ve listened to my share of Yngwie Malmsteen and Cacophony. Heavy metal fans are certainly very proud of the raw technical skill (which is, in fact, just speed) of their players. But it&#x27;s a sort of pissing contest, who can play the riff or the solo faster is not a good meter of one&#x27;s musical talent or skill.