To me, it does have a clear and definitive conclusion, which is that mere intelligent output does not mean you are replicating human intelligence, or any higher order mechanism such as consciousness. We don't know enough to tell that it doesn't have any consciousness, but that's beside the point.
You mentioned that a computer that could simulate every molecule of a human brain would also likely replicate sentience. Of course the tricky part is how do you prove that assertion, if all you have is output? If I transfer your brain to an advanced computer as you describe, can I conclude that you're conscious based on what you tell me? I don't think so, because with present technology I could likely make a passable version of your writing output with a LLM. To me that's the real value of the Chinese Room, which is to expose precisely this dillemma. People wrote all sorts of replies to it in order to tackle that - you may be interested in reading about Dennett's p-zombies if you haven't already.
There's string circumstantial evidence that we do. And really "computers can simulate the physics in the brain" is the null hypothesis.
In any case why is the Chinese Room always stated as if it has a clear conclusion rather than "this doesn't really prove anything" if we don't know enough to say either way?
> And now that we have almost literally developed a Chinese Room
I don't think so. The GPTs are currently still very far from the complexity of the human brain, and they are missing many features that may make a big difference to consciousness - for instance the ability to learn while running.
So while it may be fairly easy to say ChatGPT isn't conscious/sentient, that isn't the question. It's whether computers theoretically can't be conscious because consciousness comes from some physical property that they can't reproduce (like quantum microtubule crankery).