Sure, but that would just mean that it’s imaginable that a rock might not have any conscious experience. Which, well, it actually doesn’t.
The zombie argument doesn’t mean that you can just make up conscious experience, or the lack of it, willy-nilly. It means that since all of the physical causality going on in a human brain can be conceived of as occurring without any conscious experience, and since that activity fully serves to explain everything about the actions of a human, it is possible for a being physically identical to a human, yet without conscious experience, to exist. Consequently, the physical facts don’t fix the experiential facts.
Sure, I even published it:
Basically, the notions of predictability and possibility don’t exactly align; we can’t derive phenomenal facts from the physical theory, but physical facts fully fix phenomenal facts. (In some sense, this is analogous to the case in mathematics: the natural numbers have certain properties that can’t be derived from any given axiomatized theory of the natural numbers, due to the incompleteness theorem. But to the extent they exist, the natural numbers still have those properties, it’s just that theories are intrinsically bounded in their ability to predict them.)