> Brains are made of neurons and thus have a property their parts do not; ergo, emergent behavior.
I think you're being too quick. Let's think about things that we know to be emergent structures/behaviors: cities, societies, the human body, ecosystems, etc. In all of them, you can recognize that the network of interactions is too complex for human intelligence to fully grasp, but you can pin-point the building blocks. It's not magic. We know how DNA directs the synthesis of proteins, how proteins fold, how they combine to form larger structures, etc. It's not possible to fully grasp the full mechanism that is a human body, or a society, but this is because it's too complicated, not because we don't know the components.
With conscious we don't have that. It's an all-or-nothing proposition. What is your consciousness made of? Can you identify building blocks? If not, then you just have faith in emergentism, but you don't have a serious scientific theory.
If eventually you can identify building blocks, and emergentism is correct, then surely these parts will belong to smaller chunks of the system. Eventually neurons are part-conscious. Otherwise how could the big thing emerge? So, in this case, there is something fundamental about matter that we know nothing about.
Or, consciousness is more fundamental than mater. Serious people have also proposed this throughout the ages -- call it platonism maybe. This is an unfashionable philosophical position theses days, but as valid as materialism. Both are perfectly compatible with current scientific theories.