Probably the most out-of-ordinary answer you'll get but that is to be expected from me, surely?
As you already know, I'm far from being "metal". Some of my favorite bands are heavy metal bands but they oddly are exceptions to the rule in terms of my valuation of the genre. I find most of the genre's bands to be very dull and generic. I find a good chunk of them childish and pointless. More often than not music goes nowhere and it lacks the atmospheric elements that suck me into the music. A lot of metal bands get too caught up with "riffing" and "soloing" that they forget about details that make music sound great. There's just a handful of truly good songwriters in the genre and all of them seem to evolve in some way as time goes by.
If I were to focus on genres of the heavy metal genre itself, I can completely write off power metal, black metal, glam metal, groove metal, symphonic metal, neoclassical metal and any metal with the word "core" attached to it. Classic heavy metal, thrash metal, progressive metal and death metal are the genres who have exceptions to the rule for me, but they're also very limited. I only like three classical heavy metal bands (Maiden, Priest, Sabbath); three thrash metal bands (Metallica, Megadeth, Testament); four death metal bands (Opeth, Death, Morbid Angel, Cynic) and one progressive metal band (Dream Theater).
Generally speaking; metal fans, along with classical music fans, are the most conservative fans of any musical genre. These genres feature by far the biggest amount of fans who say "I don't listen to anything but this genre". You can see metal fans dissing off any other genre, calling them garbage, praising metal musicians who do so everywhere. Bruce Dickinson, who obviously listens to shitloads of stuff that are not metal, feeds his crowd with claims like "It's metal or bullshit". He knows what he's doing. By conservativeness I don't just mean constant bashing of genres which they see as "threats", but also the constant pressuring of bands to go "back to basics". A very significant amount of people bash Maiden for their stylistic changes in the 21st century, Metallica for their sound change in the 90s, Opeth for trying out progressive rock and the list goes on and on. Same people tend to praise Megadeth for being stuck in the same sound for over a decade and failing to produce a groundbreaking album. They're "consistent" and have not "sold out", so they claim.
As I've said, some of my favorite bands are metal bands. My Top 10 would feature more metal bands than any other genre. However, my overall taste in music is far from the classic metalhead taste. You can see me singing along to 80s synthpop hits, enjoying some old school hiphop, be absolutely blown away from stuff like jazz fusion and prog rock which many metal fans would consider boring, listen to a lot of traditional folk music, etc. I'd rather say "I'll listen to anything that sounds good" but that's the slogan of the casual music listeners who don't know a crap about the artists they listen to, so I go with "I'm a rock music fan" instead.