Yes, what people are trying to point out here is that a subjective experience is always "real" to the subject, because if something isn't "real" then you couldn't have just experienced it. Even if it's just a fireworks of neurochemistry it's still real, as an experience.
But what the skeptics are trying to do is point out that something that has the definition of "real" must exist in a measurable space somewhere, either in this dimension or another one. Meaning that 2 separate observers can inhabit the same space and make the same observations.
But that definition of "real" makes sense only because we humans have gotten so used to living in this seemingly measurable and concrete 3-dimensional reality. But even quantum physics is starting to point out that anything you measure is affected exactly because you're measuring it (Heisenberg uncertainty principle). So measuring things and therefore getting "evidence" just seems like a completely meaningless human concept. Sure these evidences are meaningful and useful in our everyday 3D lives, but were talking about the frontiers of the unknown here.
The thing I'm trying to get at here is that it doesn't matter if an experience exist in a measurable space or not, it still exists because it
is being observed by an awareness, which is you. Reminds me of something that McKenna said: "You're witnessing something that no-one has ever seen, AND what no-one will ever see again!". So sorry there's no passengers to be taken for these trips. And no measuring to be done.
Then again never say never. If the
visual reconstruction stuff ever becomes a proper science, then we may find out that atleast the visual aspects of hyperspace can be recorded and measured. But I have a strong feeling that when we enter hyperspace, that thing would just show static.