Well, I won't say you have bad taste. But you'll probably like what I will say even less.
I would say you're ignorant about music. Metal, regardless if it's death or black or doom or prog or whatever, is still a very,very narrow and conservative style of music. That's why it's all called "metal." Metal is an extremely limited subgenre of rock that has long relied on some very strict conventions. Those conventions have been recycled to death and in order to make it interesting, bands have resorted to very superficial tactics, like speed it up, slow it down, use 7 string guitars or dropped tunings, add some meandering "improv" in the middle that they mistakeningly call "jazz," get a keyboardist to add some ambient drone or a second vocalist who can actually sing (as opposed to grunting, snarling or screeching), add flutes, whatever. I was a metal fan for a long time myself too (I had close to 1000 CDs of different metal from the 80's up until the mid 90's, and that's not including my LP, EP and demo collection - it was an obsession), and I've pretty much heard it all. .
But at the end of the day, it's all just metal. Sorry. You have hardly the diverse taste you think you do if this is the majority of music that you listen too, even if you name 1,000+ bands. You just like the conventions that metal employs, and it's likely that whatever else you listen to that's not metal uses very similar conventions. It's like someone saying "I love literature, but I mostly just read romance novels." Anyone who knows literature would laugh that that, just like anyone who knows music would laugh at someone saying they love music yet listen mostly to metal.
A fellow musician once told me, "I've always found that people who truly love music like a wide variety of music." As a musican with a varied background (classical, early music, jazz, blues, folk, world music and rock), I can say that's true, without a doubt. There is an entire universe out there of really great music, and you're content with a closetful of very limited and often mediorce (if not bad) music. And that's a very ignorant and arrogant attitude to take, one that's sadly commonplace among metal fans, as I've experinced. That's one of the reasons why I don't like metal anymore (in addition to being thoroughly bored with it) - the fans as well as the bands themselves tend to be, well, bigots and morons, to be frank.
Now if that's the kind of music fan and person you want to be, if that's what you want to spend your time listening to and limiting yourself to, fine. God knows I know better than to try to broaden the mind of a metalhead. But please don't try to pass yourself off as having "diverse" taste.