You’re talking about Cartesian mind-body dualism. It’s absolutely fine to not sneak in that view into an otherwise sound thought experiment, as it’s quite irrelevant—the concept of p-zombie from Chinese room experiment holds regardless.
> The argument is not "mostly successfully", it's identically responding.
This is a thought experiment. Thought experiments can involve things that may be impossible. For example, the Star Trek Transporter thought experiment involves an existence of a thing that instantly moves a living being: the point of the experiment is to give rise to a discussion about the nature of consciousness and identity.
Thing not possibly existing is one possible resolution of the paradox. There may be a limitation we are not aware of.
Similarly, in Searle’s experiment, the system that identically responds might never exist, just like the transporter in all likelihood cannot exist.
> The entire point of the chinese room is that from the outside the two things are impossible to distinguish between.
To a blind person, an orange and a dead mouse are impossible to distinguish between from 10 meters away. If you can’t distinguish between two things, it doesn’t mean the things are the same. Ability to understand, self-awareness and consciousness are things we currently cannot measure. You can either say “these things don’t exist” (we will disagree) or you have to say “the systems can be different”.
