Regarding IIT, I can't believe just how bloody stupid it is. As Aaronson says, it is immediately obvious that this idiot metric will be huge not just for human brains but for a lot of really straightforward systems, including the tea spinning in my cup, Jupiter's atmosphere being hyper conscious, and so on. (Over sufficient timeframe, small, localized differences in the input state of those systems affect almost all the output state, if we get down to the level of individual molecules. Liquids, gasses, and plasmas end up far more conscious than solids)

edit: I think it's that you can say that consciousness is "integration" of "information" whereby as a conscious being you'd only call it "integration" and "information" if it's producing something relevant to you, the conscious being (you wouldn't call it information if it's not useful to yourself). Then you start trying to scribble formulas because you think "information" or "integration" in the technical sense would have something to do with your innate notion of it being something interesting.