I think that suffers the same flaw as logical positivism: if my axioms can't find a difference, there isn't one, no way my assumptions are wrong. (Namely, my axiom is that external observations capture the entirety of reality, there is nothing subjective.)
If two people laugh at a joke, one faking and one actually finding it funny, what is the externally observable difference? Assume the faker has been trained in all manner of knowledge about what would make the joke funny, they just don't find it so.
I don't really find the Chinese Room argument very compelling because there are too many "it's obvious that X can't really understand" in it.
Also, you can't derive from it that there can't be computed consciousness in some other form.
The system's response is trivial: Sure, if the room+person combination leads always to a coherent response in Chinese, then the entire system understands Chinese. I'd go even further: If the person in the room does not understand Chinese, but the system does, then there is some entity that understands Chinese - either a person or an advanced AI, feeding the inputs. Then, from the systems perspective, the person in the room is largely irrelevant.
But this is not the argument: Despite no discernible difference from the outside, the person in the room may either understand Chinese, or they may not. And so there is a distinction - from the perspective of the individual in the room, that does not depend on the outside observation.
That's all there is to it. It shows that meaning and understanding are not the same as syntactic computation (an important point, to be sure), but it does not show that one can exist with or without the other. By extension, it does not otherwise disprove consciousness as being this or that.
The analogy might be more valid if arguing its not possible for a third party to actually determine whether an entity/system is conscious (irrespective of whether the entity is conscious or not)
Instead, the core matter is about form versus meaning - something that is indeed not observable from the outside, and yet is a distinction to the person inside the Chinese room.
Edit: Or as fouronnes3 said in a sibling comment, why it's actually evidence against Searle's original argument.