Yes, W4U hit the nail on the head about "nothing at all" after death. People who claim they have no dreams could be basing that on a persistent lack of ability to remember them -- a kind of missing time between falling asleep and waking up. Maybe they don't, maybe they do. Being dead is the ideal non-consciousness, where one can be assured (at least according to anti-panpsychism orientations) that there are no dreams, thoughts, perceptions, feelings. And the deceased brain isn't even generating the auditory blankness and conceptual awareness of silence, the empty "screen" of blindness, etc. Basically a return to the non-mental character of matter in general (neither manifested nor understood). A conventional materialist (as well as most people) will assert that the world still exists, it's just "invisible" to itself when minus the manifestations of experience and identifications of cognitive activity. However, there are eccentric materialists like Galen Stawson who are panpsychists or protopanpsychists. In those versions atoms or molecules or interactions or the EM field pervading space (or whatever) may have primitive "shown events" associated with them. But presumedly without any cognitive organization that could validate that they "are there". Such accordingly serves no purpose other than to explain what the complex experiences of brains emerge from, or to assert that matter or the universe does not utterly exist in an "absent to itself" manner (except for organisms and any conscious AI). Even though the experiences/manifestations a brain is having are publicly undetectable no matter what level a scientist is working at: particle physics or neural tissue. That's why the idea that consciousness doesn't exist may carry weight in some corners of the academic world (when "consciousness" is narrowed down to that specific facet, the intellectual operations set aside that aren't dependent upon phenomenal expression).