I could probably list off 50+ death metal (or similar ticky-tack 'subgenres') bands that I'd listen to on a regular basis if it wasn't for the vocals.
Not sure if that is what you were getting at or not.
Today's death metal is not the same as it used to be. At the beginning the lyrical content was more important than the speed of instruments. Now it is battle of bands on how fast can you play guitar or drums. That's why I hate modern death metal.
There's lyrics in death metal?
As a singer myself I have to like the singer, no ifs,ands, or buts about it. They don't have to be technically proficient, they doesn't have to be pretty, they just need to catch my ear somehow.
I'll give you a great example of a cool band that completely turned me off because of the singer:
The first time I heard this song I was like "Yeah, that is really cool sounding." and then the vocals came in and I went "Oh, that's a shame."