I think so! You independently stumbled upon the "China brain" thought experiment. https://en.wikipedia.org/wiki/China_brain - is "the nation of china simulating a brain" conscious?

Your brain is a network. How does your entangled fatty tissue achieved consciousness?

I think that until we can answer this question in the authoritative way ruling out non-brain based consciousness concept is not particularly well thought thought - after all plants exhibit communication and response mechanisms that are similar to those in animals - without brain.

So what's your theory of consciousness and how does it preclude absolutely everything except wetware you generously include? :)

I think this comes from our rather nebulous definition of "consciousness".

We have this natural tendancy to impose our feelings of self on the definition of consciousness. Its hard to accept that all of our thoughts, emotions, and behaviours could be calculated by a human with pen and paper (with enough humans and developments in neurobiological research).

I believe we will have to reckon with these loose definitions and eventually realize how lacking in utility they are for describing engineered intellegence.

This question boils down to whether consciousness is emergent from physical substrate and processes or not. If so, then yes, anything can be conscious, if not, you probably believe in spirit.