Most of the "symptoms" of near death experiences are generally considered to be relatively well-understood side-effects of our neurophysiology. Back when the military was doing "human limits" testing (i.e. finding out the range and nature of human physiological limits relating to temperature, pressure, acceleration, etc.) somewhere around the middle of the 20th century, they discovered that certain extreme activities (e.g. high-G compression) could reliably produce "near death experiences" in the test subjects. Further study of the phenomenon has basically shown that it has to do with the peculiar way the brain starts to shutdown when deprived of oxygen. The particular location of the visual cortex in the brain makes it particularly susceptible to generating artifacts under anomalous conditions.
This doesn't discount anyone's experience, just puts some perspective on it.
Thank you so much for your post! Indeed, I was already aware of the neurophysiological explanation of near death experiences but hadn't heard the one about the G-force. All of it is interesting, and physical cause is a necessary tenet to the metaphysical naturalist worldview. Many of these neurophysiological theories invoke the recall of existent memories.
IMHO, the "fly in the ointment" is that NDEs are experienced by children who have no such memories, and that some of the NDEs feature accurate out of body accounts, i.e. from perspectives other than the location of the body at death.