They don't. It's normal visible light spectrum, just extremely weak. Nobody can see it with their eyes.

Supposedly the human eye can detect a single photon under the right conditions though.

Not really... https://www.technologyreview.com/2017/08/08/105518/the-thorn...

Or, yes, under ideal conditions, maybe sometimes. 51.6% chance of being right in a yes/no question will not help in this case.

Nobody is a pretty strong claim.

Human bodies are different in many ways.

This is like saying: "Nobody can jump over this 200m wall. - Nobody is a pretty strong claim." It's really beyond the scope of human vision overall, rather than "really hard".

Those are ... two different things?

People can pick up single photons, this is definitely within the realm of possibility.

Btw, your level zero snark can be defeated by the "on which planet?" argument.

Or perhaps there just happened to be an overlap between the nonsense they believe in and some shred of truth that you have to squint really hard to make work.

That's not even the "BS" part (for me), but what they "derive" from all of that.