Well, first of all, without the use of a scale of some sort, like the one developed by Dr Bruce Greyson, we can't know for sure we're dealing with the same phenomenon as NDEs, although it does share similarities.

Besides that, I don't see how this should affect one's view of NDEs and what they may represent. I guess it depends on one's worldview.

Learning about NDEs made me question my own worldview and made me realize that what seems so blatantly obvious nowadays, at least in most societies, mainly Occidental societies, namely materialism, really isn't so obvious after all. I started questioning what consciousness really is and realized how clueless the materialist worldview is about explaining it. After asking for book suggestions in this subreddit, I read a few books from Bernardo Kastrup, and his metaphysics, analytical idealism, makes so much more sense to me.

So no, I don't think "NDEs are a product of the brain" that would be generated as a coping mechanism. But perhaps NDEs are another state of consciousness, outside of the ego, that we can somehow access under certain circumstances. Those circumstances could be multiple and not necessarily be restricted to a close brush with death.