This is like declaring there is absolutely nothing inherent in the nature of matter to have temperature. Anyone making such a declaration would be looked at strangely if they wanted to enter a discussion on the nature of temperature.
Declaring from the outset that there is anything particularly weird about biological systems being conscious, when one of the most basic, widely-accepted facts about biological systems is that they can be conscious, is not a good move. It sets up the problem as a Big Mystery, which is what the OP is pointing out.
There are some "problems" that many people are never going to accept the solution to. Every few years someone publishes "the definitive answer" on the Mona Lisa's smile, and I still see people asking, "does nature or nurture cause behaviour?" as if it was a serious or interesting question.
Likewise, there is a very significant chunk of the population dedicated to the proposition that "consciousness is fundamentally mysterious", and one day when we have it worked out pretty well why some complex systems have this emergent property, those people will still be ending articles on the subject with coy gibberish about how "...in the end, you can't reduce the magic of conscious experience to an equation."
Sure you can. And we will, in the same way we came to understand temperature as an emergent property of systems of interacting particles in closed systems, without recourse of phlogiston or caloric or any other thermodynamic secret sauce.
That, right there, is why I reject this kind of argument. It's not parsimonious. Temperature isn't an "emergent property". It's a name we've given to a measurable phenomenon; in fact, it's the name of the measurement, itself.
Another un-parsimonious notion: "one of the most basic, widely-accepted facts about biological systems is that they can be conscious". Okay, if they can be conscious, what makes one conscious and another not? Why am I blessed with the gift of consciousness, but my cat isn't? Or if she is, why her, but not the spider in my bathroom she loves to torment? Or if it is, why not the bacterium on my toilet seat?
Drawing imaginary lines somewhere in the middle of reality and saying "things on this side of the line have squooblith, but things on that side don't" is going to require a bit of explanation as to why the line is there, and not somewhere else.
For myself, the most parsimonious answer I can find to all this is that consciousness is an intrinsic property of matter, itself. So, sure, a rock (let alone a molecule of gypsum) is going to have a markedly different kind of experience than I do, what's to say that it doesn't have some kind of experience? It also nicely eliminates this "mystery" everyone seems to be down on: what could possibly be mysterious about something that is literally everywhere?
But that's just me, and I readily admit that I'm rather anomalous, have studied this stuff for far too long, and taken a nontrivial amount of psychedelics. So, you know, grain of salt, &c.
Consider Conway's Game of Life. A few basic rules and you end up with remarkable, emergent complexity. The game of Go is another beautiful example.
The same is true of any number of phenomenon. Break them down to their basic elements and it's not clear how the emergent properties arise, and yet they do.
So is the brain just "meat"? Maybe. But that doesn't preclude incredible emergent complexity.
Why can't we just declare it an open question in neuroscience and cognitive science?
So, please, yank my sacred mystery out from beneath me: what's the explanation?