It does bring up a question of what "brutal" means, though.
I've thought about this too. 'Brutal' in metal means a lot of things and has so many meanings that at this point--as a musical descriptor--it isn't very helpful out of context.
Looking at Metal Archives, most death metal bands with wholly unintelligible vocals are labelled "brutal," but really, that's limiting and sometimes wrong.
Example: Vomit Remnants is "brutal" and Krisiun is not? The earlier is good groovy death metal with puke vocals, and the latter is often an unrelenting barrage of notes & hits.I like both bands, but to say Vomit Remnants is more "brutal" seems to go against what that word even means.
And albums by (brutal) Pathology (who I like a lot) are far more catchy and groovy than something by Hate Eternal, who are also described as "death metal," sans 'brutal.'
In metal, the word brutal is starting to lose its meaning.
Personally, I tend to describe music that ASSAULTS THE LISTENER as brutal, whether it's death metal or not--- 1349, Insect Warfare, The Kill, Krisiun, Wolf's Lair Abyss, Revenge, Axis of Advance, (Mexican) Disgorge, etc.