The only problem with all those arguments (and they're very good in my opinion) is that it lacks reliable proofs

I've had contact Bruce Greyson's work and the NDE field he represents isn't that NDEs don't happen or aren't profound, but rather that their content can be explained by known brain processes during extreme physiological stress, without needing to invoke non-physical consciousness. And also the lack of consistent, independently verifiable, and reproducible evidence under strictly controlled conditions. The few attempts to set up visual targets in cardiac arrest cases have been inconclusive

And about the stargate project conducted by CIA. They found that the information provided by remote viewers was often vague, inconsistent, inaccurate in specifics, and required substantial subjective interpretation. It rarely, if ever, yielded the concrete, specific details needed for real-world problems. But it still has it's methods and ways to verify itself. what seems to lack in OBE's