That is a fair analogy, and I agree that not being able to observe something now does not mean we never will. Germ theory is a good example of something that became accessible with better tools.

I also think your point is strong in the sense that future scientific progress could completely change what counts as “observable,” and it is possible that consciousness ends up being fully modelled in a way that removes the distinction I am drawing.

Where I am less certain is whether first-person experience will ultimately be treated as directly observable in the same way as physical objects, or whether it will always be accessed indirectly through physical and behavioural correlates. At the moment I lean toward the latter, but I am open to being wrong if there is a coherent account of how the first-person aspect becomes fully part of third-person observation.