I put it to you that all existence always involves relationship between observer and observed
Well, of course.
(speaking as one who is totally uninformed in the philosophical applications to the "mystery" of why are we here & what meaning exactly are we to make of our temporary existence ...)
Might I say (before you dazzle me with your knowledge
) that there might be many different approaches to reaching a workable (for each individual) understanding.
Me, I form my meanings & understandings through literature, art, much reflection, talking constantly to people who are trying to come to grips with the very same questions ... you approach the same questions through reference to Great Philosophical Minds who have grappled at length with the same questions. And use a special language to communicate their findings.
It strikes me as a great shame that your side of the fence & mine seem incapable of communicating what we have learned. Because, I suspect, we might have much to offer each other, from our very different perspectives. For starters, the language we both use is entirely different.