Unfortunately, the fact that Dr. Assante has to even discuss the subject of religion in a book on the afterlife is because we as a society relegate the entire topic to that of religion and belief. Our beliefs in, and notions of, the afterlife are largely wrapped up in our notions of divinity--along with ideas of moral worthiness ("if I'm a bad person, I won't go to heaven"). Dr. Assante tries to decouple this association, for good reasons--many of our beliefs on the "afterlife" are simply not accurate, just as our notions of "God" are probably inaccurate (or flat-out wrong, as is the case with some). And these erroneous religious beliefs contaminate our ideas of the afterlife--not only now, but in the hereafter.
Which brings me to something that Dr. Assante has observed, which, to my knowledge, no one else has addressed: Primarily, accounts by survival personalities (via mediums) never talk about the wondrous being of light that is common in NDEs. Also, there is no past-life flashback review described in these communications. (These descriptions are also absent from hypnotic past-life regressions.) I've wondered about this for years, even to the point of causing me to doubt the authenticity of much of mediumship material. Over time, I've developed my own theories of why this might be, but Dr. Assante has some interesting ideas on this.