What? Dead Congregation, Morbid Angel, Hypocrisy, At The Gates, Pestilence, Death, Suffocation, Immolation, Origin, fucking a lot of others disprove that idea. They all have a knack for song placement and album flow. Often with semi-coneptual lyrics (I.e. Hypocrisy sticking to alien shit and da devil or Origin and fucking space sex or whatever cuz who pays attention to their lyrics anyway). My point is a large chunk of quality death metal is more thought out in this regard than you must be able to realize.
Death metal anthems? Hammer Smashed Face for sure. Roswell 47, Spheres of Madness, Dead By Dawn, and everyone sings along with God of Emptiness when the video is played haha. Baby Killer, maybe. I Don't Care, Pull The Plug, The Exorcist, You'll Never See..., Override of the Overture or Sickening Art, Corporal Jigsaw Quandry.
Maybe they aren't anthemy, but all of them have their own catchy hook in some way. Every one. Tell me death metal doesn't have fucking hooks. Hell, a lot have generic rock structures (Verse/chorus/verse/chorus/bridge or solo etc)