Ok well first off I'm not sure if ignorant is the right word. What you're describing is closed mindedness. Secondly it's all a matter of opinion so there really is no right or wrong answer to what's good or what's bad. The only real wrong reason to listen to something would be if it's only to be part of a trend which is something these kind of people are hyper aware of. I'm not saying other forms of metal are trendy but I am saying that being true to yourself and not caring what other people think is a big part of metal culture. Now lastly by saying that by not listening to more than one type of metal makes you not a metalhead you're passing judgment and being hypocritical. Still I agree metalheads should be more open minded, but of they don't want too it's their loss. I don't give crap what anybody does.
You must be young. Most people like the genre of music they grew up with - usually high school thru college. That's when the songs had some meaning to them and take them back to that place. Screaming is not a vocal ability - it is just the ability to scream. If someone wants to sound like cookie monster, I have no problem with it, but I don't consider it a talent unless they knew Jim Henson. As far as the double-bass issue, I think it makes a lot of the songs sound too similar. And, once you reach a certain age, it probably triggers heart murmurs as well. Like whatever you want to like and like two or three genres if you want, but don't call people who like what they like stupid.
I am a fan of Heavy Metal Music and I am not ignorant; I prefer Thrash Metal, Speed Metal, and last but not least I prefer Melodic Death Metal. I hunger for double bass beats and sweet guitar solos over a drum machine.
People have different tastes. Some people like heavy metal only. Some might like thrash metal. Some might like deathcore. Some might like all of them. Some might like only a few bands from the metal genre, like as you said, Priest and Maiden. That doesn't mean they're ignorant of the fact that there's other types of metal out there. That doesn't mean you can judge every heavy metal fan out there. And what's with the whole true metalhead thing? As long as you listen to any kind metal and enjoy it, you're a metalhead. End of story. So basically, heavy metal fans are not ignorant. Heavy metal might just happen to be their favorite among many metal subgenres.
I wish to explain why each genre is disliked but it's not worth the time, strict heavy metal fans (60s-80s metal) are locked in the era, as someone else said it may be from what they matured along with. Those who are younger probably learned it from their parents or older sibling/cousin. Why is it okay for people to hate certain genres or even only like one? Because metal is incredibly diverse, it eclipses any other genre with what elements its willing to work with, some people will only like the more mainstream radio metal, some will only like early black metal. This diversity does come at a cost, it's difficult to start listening to new genres. It's hard to get into the more extreme genres and some who are not able to get over the hump into a new genre or plain dislike it will set their own preferences that much higher on a pedestal till they become very close-minded. Don't let it get to you, hate and let hate, opinions come in the billions in metal, like I think most metalcore, deathcore, djent, radio metal/hardrock, pop metal, glam, etc are complete and utter garbage but love prog, death, tech, thrash, power, heavy and avant garde. It's just what we are
