I was talking about something a little more empirical. Like, literally, does my g-protein consist of exactly the same amino acids chained together in the same sequence, and folded identically? Some minor mutations don't always make the protein non-functional, not all would result in color-blindness. I thought this was the basis for tetrachromats anyway, just with a different protein (and a more significant mutation).
Same with "firmware". If our brains process the data differently, then our actual perception might vary in (eventually, I would hope) real-world measurable ways.
That path leads down to solipsism which is not very intersting