I agree that those peak states of consciousness are often powerful and indeed overwhelming. I've listened to dozens of Terence McKenna lectures, and I've even had some some odd experiences while high on cannabis, which I've written about (some links below). I view psychedelic states as the true sources of religious experience, and I suspect that NDEs are similar. While we're high, we can believe any odd thing we can imagine because the drug lowers our guard. But in the light of day, we must account for all the evidence, not just for our private experiences. That means fitting in the experience with science and philosophy.
Anyway, I don't discount the possibility that science is missing something fundamental when it comes to consciousness, but the alternative theory that takes NDEs to imply an afterlife must meet a high bar, assuming we value rationality and critical thinking.
Often, these disagreements come down to epistemology. What do we think knowledge is for, and how do we assess knowledge claims? I'm pragmatic about empirical models, although I distinguish between what's true and what's artistically or aesthetically powerful. Religious myths can be powerful, like great fictional stories, without being literally true.
https://therabbitisin.com/godhood-through-cannabis-a9f838c38b53?sk=17ba93f6ec4d4c824123daa3b3637426
