When I watch a magician do a magic trick, I am "really" watching a magician perform a "real" magic trick. I am "real", the magician is "real", the trick is "real", and the different experience each of us has of that trick's happening is "real". In fact, NONE OF IT WAS UNREAL. The magician really is a magician, and the trick really is a trick, and I really was fooled by it even though I wasn't really fooled by it because I knew it was a trick.
I say all this to try and get you to understand that reality is all there is. Misperceived, misunderstood, mistaken, mislabeled, or whatever else; it's all "real". There is no "unreality" vs "reality". A theory about reality does not exist in some realm apart from the reality it's about until it's "proven to function" by some physical mechanism. The sound of a train horn does not exist apart from the ear that hears it. They are conjoined phenomena. In fact all of existence is a conjoined phenomenon. All the "parts" of it that we perceive are only being perceived as 'parts' in relation to all the other 'parts' of it that we perceive in relation ... you get the idea. In truth, it's just one big complicated phenomenon taking place in an endless sea of 'nothing else'.
Once we understand this: that any 'knowledge' (of existence) we can seek is contextual, we can begin to see what the philosophers are debating, and why. They are debating the contextual validity of a proposed truth-claim against those of other proposed truth-claims. Because philosophers understand that "truth" is a moving target: that it's contextually dependent. And the contextual possibilities are endless, given that the complexity of existence is endless.
Shoot, I thought I was arguing that reality is all there is. Clearly, I am struggling to make myself understood.
I want to explore the train horn analogy a little bit. I could concede that for there to be a sound, there must be an observer to hear the sound, if you want to have a strict definition of the meaning of 'sound'. But I assume you would agree that an expanding wave motion of air molecules still occurs when the train whistle is activated, regardless of whether there is an observer to sense the air motion.
As to truth, I don't see it as a moving target. I think of it more as building a picture that has no defined boundaries. The center of the picture has the highest detail and represents that knowledge with which we hold the most confidence. As we move out, we begin to lose detail and the picture devolves into mere sketches or simplistic outlines or in-descript shading, highlighting the boundary between what we know and what is completely unknown.