I think you misunderstood. I'm not objecting to the idea that mind is ultimately made of matter. I'm objecting to labeling it as a "state of matter", which has an entirely different meaning. (It does NOT mean "here's a bunch of matter that interacts in an interesting way.") The paper's abstract even explicitly states:

> We explore five basic principles that may distinguish conscious matter from other physical systems such as solids, liquids and gases: ...

So it seems clear that the author argues "being conscious" is parallel to "being liquid", but this better have a really solid (no pun intended) justification.