Yes, I think you have a point that for it to be an illusion “something” has to perceive it.

I also think your reflection on consciousness being a some sort of process is interesting. Is it a “machine” process where one input+state always results in the same output? Regardless of the answers implication on agency and choice, the mystery is still that I feel aware. I cannot speak for you, but I think you’d tell me the same, even if you cannot prove it to me.

Regarding the emergence I think one aspect could be scale, and said emergence might not be binary. I listened to a Lex Friedman(think what you will about him) podcast episode with Michael Levin from Dec 3 which talks about things along these lines. Not directly related perhaps, it might be more geared towards intelligence, but you might also find it interesting.

I read it as consciousness being more of a “side effect”, rather than the thing a controls actions and “making choices”. So consciousness would then be more of a passive effect than driving change.

In that sense the illusion would be that consciousness has any agency, when it is instead a passive experience, a perception of control.

Well, go on a tell us the real story then.