I think metal is one of those genres of music that always has a hardcore solid group of fans. Every once in a while it pops up into mainstream music only to later fade back to that core group.
What's interesting is that the Buffalo-Niagara region where I grew up has a pretty vibrant metal scene. I remember when we were gigging around and the only acts we would ever get paired up with at shows were either metal bands or emo punk (or some other version of punk). We never really fit into either scene. We did some heavy distortion in some of our songs, but not really a metal band, and definitely not punk. Not sure what we were.
Most of the people I know within a decade of my age from back there are huge metal fans. My sister and her husband were legit broken up when Lemmy died, almost like a family member. Most of my friends from high school were listening to Metallica before they were popular too. It's almost ubiquitous there from my point of view.
One of our friends' metal bands Plain of Ashes had a guitarist named Mike Hatalak that went on to play in another metal band called It Dies Today. That band never really made it big as far as I know (whatever that means any more I'm not sure) but I'm pretty sure they toured nationally for their releases and had some mid level success, you know, actual professional musicians. I remember talking to Mike at a house party about it when he first joined. He seemed excited about the project. Lost touch since obviously. Point being, lots of metal heads in Buffalo.
I actually just looked them up. Turns out they had more success than I knew. https://en.wikipedia.org/wiki/It_Dies_Today Had music in hit films and video games and stuff.
It Dies Today
It Dies Today (sometimes abbreviated "IDT") is an American metalcore band that formed in Buffalo, New York during September 2001. The band achieved popular success in 2004 with the release of their debut album, The Caitiff Choir. After frontman Nicholas Brooks departed in 2006, just after the release of the band's sophomore effort Sirens, It Dies Today released Lividity in 2009 before going on an indefinite hiatus in 2010. However, with Brooks' return in 2012, the band have re-formed and have begun recording new material again.