Hmmmmmm, so:
1. We gotta be a bit more robust about what it means for a model of a thing to fully produce the properties of that thing
2. We gotta separate the hard problem itself and *why the hard problem is hard*
For #1, it's not just that the model "feels like it fully and clearly identifies X with Y", nor is it that the model has been confirmed through sufficient empirical evidence to match observations of Y. Rather, it is that, mechanistically, we can articulate precisely how it is that the model and its structure interact with other physics objects to produce the properties that we observe in Y. (and then, since many models can have a good mechanistic explanation and still be wrong, we do still need to confirm that model with empirical observation; but the empirical confirmation piece is not the issue imo).
Here, it starts to matter how we define the objects we are pointing at. So, for example, one way we might define water is "that thing that makes up the primary liquid of the world's oceans". This is essentially just an ostensive definition, and we can just look at what the oceans are made of, do some science, and find that it's this molecule with two hydrogen atoms and one oxygen atom. Badabing badaboom. No mechanism required because all we did was point at an object, then investigate it's nature directly and find that it is this particular thing with so and so structure.
BUT. Imagine we instead define water as: "that liquid which is clear, non-toxic, acts as a universal solvent, weighs ~1 kg at room temp, boiling point at 100C and freezing point at 0C, etc etc." Realistically, this is more what we mean when we say something is water ex ante. If, for instance, we encounter a new liquid, and we want to determine if it is water (without actually testing if it is H2O ofc), we can't use a definition like "is the liquid that makes up the oceans", because this liquid isn't from the oceans. So we have to use the known properties of water.
Now, with this definition, what it means for our model of H2O to produce the properties of water (i.e., for it to explain why water *is the way it is*), is that somehow, our model of H2O can provide a mechanistic account of how properties like clearness and solventness come about. So we can ask "why is water clear?" and then with our H2O model we can say: "well, what we mean by clearness is that an object allows visible light to pass through it, and H2O is a molecule that does not absorb much light in the visible spectrum because XYZ, and so appears clear in small amounts." Thus we can explain water's properties via its nature.
Playing the same game with qualia: if we define redness merely as "that thing which occurs when humans report seeing red", then maybe we can equate redness with a specific brainstate. We need no mechanistic explanation for why redness "is the way it is" because we have only defined redness ostensively.
But if we define redness as "that phenomenon that has the property of redness" you can see that now we need a mechanism that explains redness as a property, rather than one that merely corresponds to redness as an object/event.
And this gets to the delta between what the hard problem is vs. why the problem is hard. If there were a way to mechanistically explain *why and how* a particular brainstate produces redness--why it is that a certain set of electrical signals or waves produces a quale, and why that quale has the particular character of redness--that would, imo, constitute an answer to the hard problem. But the hard problem is hard because it seems, in principle, impossible to give an account that does this. Like, how do you get from properties of an electrical signal or neuron activation state to the character of color or pain? Any explanation would, i think, leave a gap, where you have to simply assert "XYZ property is redness" without explaining *why* it is redness or why redness "is the way it is".
One big reason it seems impossible is because qualia like redness seem irreducible--the "way it is" seems impossible to specify, despite how distinctive it is. With clearness, we could say "well, what we mean by clearness is that it allows visible light to pass through it", thus translating the named property into a specific type of physical event that we can then connect to other physical events. But what do we mean by redness besides redness? idfk. The property itself seems inscrutable. What are the necessary and sufficient conditions for some quale to be red? What is it made of? How do we complete the sentence "what we mean by redness is..." in a way that isn't merely ostensive?
I could say a bunch more here, ofc, but will try to avoid too many tangents. The main point here is that it's not that our brainstate model lacks the clarity of identification that our H2O model did, but that it fails to explain the relevant characteristics of the explanadum.
Buuuuuut...okay one tangent for fun: which is that I do kind of agree with your claim that the hard problem doesn't matter--at least in the limit. For example, we could, in theory, solve issues related to AI consciousness by answering the easy problem alone. And there are some conceivable explanations of consciousness that would still fail to solve the hard problem and yet be so thoroughly explanatory that you kind of can't reasonably ask for more.
So, okay, imagine if we discover some new quantum field--the qualia field--and we show that certain brainstates emit qualtons (and ya know, fuck it, we're playing make-believe, so let's say that they interact with the Higgs field and solve dark matter/energy while we're at it). And then we show that when we experience vision, what's happening is that a rough grid of qualtons of various frequency is being emitted in the nearby qualia field. These frequencies are shown to correspond to colors, and the grid is just what we see. And within the qualia field there are special excitations known as soultons. And they correspond to our true self/identity, and when a qualton is emitted it forms a bond with the nearest soulton, and that bond is our access to the qualia in question.
Technically, TECHNICALLY, there is still a further question of "okay, but why are qualtons accompanied by experience? and why does the low frequency visual qualton have the particular redness characteristics that red has?"
But like, idk man, cmon. At that point we would be able to explain so many properties of experience--e.g., why visual qualia appear to occur in a 2D plane, how the 1st person perspective arises, why it is inaccessible to others, etc. I call that solving consciousness. We're done. Pack up your bags and move on.
(but we are nowhere close to such an explanation, so there are still plenty of hard-ish problems left)
(also note that such an explanation would entail that qualia (technically qualtons) are ontologically distinct from brainstates, meaning that if we had evidence that demonstrated the ontological equivalence of qualia and brainstates, we could rule out such a theory. but we can't. yet.)
(okay, i'm finally done. sorry.)