I wrote this post as a reply to a Facebook friend who was (correctly) criticizing the fashionable notion that all religions say the same thing. It seemed worth sharing here, if only because it saves me the trouble of writing something new.
I think all religions are the same in one sense. They all seem to involve getting in touch with one's higher self. This higher self may be identified as God, Jesus, one's Buddha nature, the Ground of Being, or whatever. Also, all religions seem to have been founded by someone who actually did get in touch with his higher self and then tried to pass on what he had learned. He may have had an NDE or a series of OBEs, or he may have been an expert meditator, or he may have experimented with psychogenic drugs, or he may have had some neurological quirk that opened up his consciousness. One way or another, he experienced "cosmic consciousness," at least fleetingly, and was able to retain and communicate some of what he had learned.
The differences among religions, which are substantial, come about because a) it's difficult even for an adept to distinguish between the wisdom of the higher self and the fears and biases of the ego, b) the acolytes are not nearly as advanced as the founder and tend to misunderstand his teachings, and c) as the movement grows, it becomes more ossified, ritualized, bureaucratic, political, and worldly.
I'd add to the above that one possible explanation of the divine figures seen by NDErs is that they are symbolic representations of the experiencer's own higher self. So there may be a consistent tendency, whether one is incarnate or discarnate, to objectify and misinterpret the higher self as an outside entity.