

It really does require non scientific information to address.
Consciousness is not fully understood. Without that, anything regarding consciousness is still at least a little unanswerable. You can’t point to when and where consciousness ends if you don’t know what it is, what defines it in the first place. Death isn’t exactly at consensus either.
That means NDEs can’t be pinned down with 100% accuracy yet.
Here’s what I know. Nobody that has had the cells of their brain break down, as in begin decomposition, has ever come back.
So, based on that, I think the NDE experience is going to be based in some kind of brain activity. If the neurons are “melting”, they can’t function if enough of them aren’t melting and you can jump start things again, they weren’t dead at all. That, to me, is the definition of death that matters: if you can come back, it ain’t death.
Considering the general amount of precise experimentation in measuring the brain and body during the process of dying is extremely thin and limited by the very process, I don’t think we have the right tools to measure anything that would “prove” anything about NDEs, only indicate some probabilities.
But those probabilities lean much harder to it being a chemical and/or electrical event.
Now, if you want to bring souls into it, you aren’t dealing with science in the first place because it is currently impossible to even detect whether or not souls exist, it is a matter of faith. It’s essentially impossible to prove they don’t exist, but there’s absolutely nothing ever measured that points to anything resembling credible proof that they do. So souls just don’t matter for NDE discussions in a framework of science. You might as well factor in what granfaloon a person is mixed up with as a soul.
I’m not saying you can’t believe in souls and still attempt science regarding death, just that souls aren’t studyable with science.
Since nothing in any NDE has ever been unique to NDEs, it does make it harder to put faith in them as something other than a physical process. Everything anyone has ever described (at least in any useful setting) as happening has also happened with the influence of drugs, magnetic fields, meditation, or spiritual practices. Probably others my brain isn’t pulling up as well that aren’t under one of those headings, but I think it shows what I mean well enough.
And that point is that if the experiences aren’t different from things you can experience while alive, why would they be useful for determining if the person had died?
I haven’t held a phone to my ear since before smartphones were a thing. Headsets existed for land lines. Speakerphone functions existed on land lines as well as early regular cell phones (as opposed to dumb phones which tend to have more functions than the ultra basic phones did back in the nineties).
I’m fairly confident that the last time I held a phone to my ear was before the turn of the century. I know it’s been that long at least since I would have while driving and/or at work. The cell I had at the time worked better by headset, and there were plenty of cheap and decent ones available