Not at all. Read the lyrics to bands like In Flames, Meshuggah, Soilwork, Fear Factory or Dark Tranquility. None of those bands regularly write angry lyrics. A lot of the lyrical content in death metal involves pretty interesting subjects. Fear Factory, for example, writes a lot of music dealing with the effect of technology on humanity. Meshuggah has a lot of songs dealing with human perspective and how our minds and opinions are distorted by everyday banality. In Flames frequently writes about a number of topics, from love to personal conquest.

To label all death metal as being "hateful" is pretty narrow-minded. Granted, there are plenty of death metal bands that write about murder, violence and atrocity. But the best ones rarely do, or if they do, they write it in such a context that the message is deeper than just a story about death.

The term "death metal" describes a style of music, not a style of message. Death metal bands are defined by the music, not the lyrics.