Interesting thought.
But then, whence does consciousness enter the scene?
Tegmark proposes that the necessary comparing of the passively received and converted data into a stream of internal electrochemical data with data that is already stored in memory, produces the emergent phenomenon of cognitive consciousness.
The brain actually undergoes a constant series of "eureka" moments, which produces a response of "I know that!", not just as an act of cognition, but as an act of recognition. It allows us to form anticipation of what comes next based on prior experience in memory. Don't we all have experienced the feeling of being familiar with a place we have never been before. This familiarity is triggered by your recognition of an old grandfather clock, or the pattern in a blanket, or a couch. Anything that may have been a comfortable (or traumatic) experience is "recalled" from memory and will trigger a chemical emotional response, as experienced in the past.
That's why I like the modern concepts of "integrated" and "orchestrated" information theories, which propose consciousness is the result of the processes that yields the emergent self-awareness within the current environment.
Perhaps an example can be found in the GPT3 interviews, where the AI defines its own abilities, which can only be interpreted as an emergent self-aware consciousness. It is not the hardware that is consciously intelligent, it is the orchestrated processing of the data, which produces consciousness?
Therefore, the brain is necessary for the processes that yield the conscious experience.
