The impossibility of subjectively experiencing one's own death?

Jack Romero asked:

OK, so, this is kind of “cheating” because I know this story exists. I read it once, a while ago now. Unfortunately, I can’t for the life of me recall its title or author and it’s driving me nuts.

I have a feeling it MIGHT have been by Neil Gaiman, but that could have been a complete piece of BS my brain made up fishing for an answer. It was really smart and challenging, though, and I’d like to read it again but for the life of me I can’t remember its author or title, only the events in the story itself. Essentially the main character is this man who’s had a rough life and done a lot of risky things. Then he notices this book. It’s by one of his favorite authors. Except it’s not a real book. It IS real – it’s clearly there – but it’s not a book the author ever wrote. It’s like you were a huge HP Lovecraft fan who had his catalog memorized… and then you found a Lovecraft book you’d never heard of before. You know for a fact this thing doesn’t exist, was never written, but here it is in a bookstore like it’s real.

So the guy goes and talks to someone… IIRC the owner of the bookshop where he found the book. The man explains this “Quantum Philosophical” concept that people can’t experience their own death subjectively, so whenever you “die”, you perceive yourself as having narrowly survived – in brief, as wave functions collapse, forcing events to be one way or the other, your consciousness gets shunted down the probability line where you DIDN’T die.

Thing is, reality might be infinite, or it might not be… but people’s lives definitely are not. The quantity of “event points” at which different decisions/events could occur (and thus, splittings of timelines down which your consciousness can travel as it moves through spacetime) is enormous, but ultimately finite. The more you “die”, the fewer probabilities exist that still have you living in them.

As such, if you “die” a lot, you end up in a really weird reality. You may even start experiencing “glitches in the Matrix”. Like the book. The Book That Should Not Be.

This part really stuck out in my mind. The person explaining this then stops, gives the protagonist this look, and says something along the lines of, “What have you been doing to yourself, you poor bastard?”

The story follows the protagonist through his life getting weirder and weirder, until a human extinction event occurs and his consciousness finally seems to run out of timelines and goes silent…

… Only for him to “wake up” again, with only the vaguest sense (if any; I don’t recall) of an interval between his last memory and his current experiences. Turns out that Earth has been discovered by a race of aliens and they’ve managed to somehow resurrect or clone this one individual… in order to consume him and add his memories to their permanent memory-stores. Or something like that? I don’t recall anymore for sure.

The story ends right after the alien formally/ritually asks him if he’s ready to be consumed, presumably because he does get eaten and his consciousness is finally able to dissipate. (Or whatever happens to timeline-depleted minds in this universe…)

When the motor of the mind stops working, it is difficult to see how one could experience anything. I have not seen a sound neurological examination of “near death” experiences so I have no idea whther we understand what happens neurologically in this case.