And a human brain is just changing physical and quantum states of the underlying material and isn't doing anything different at that level than any other pile of meat.
I think a human brain is quite a bit different from any other pile of meat. But a computer running an AI versus the computer running TurboTax is the same thing. They're running through the same set of instructions, swapping the same bits of data in and out of memory.
Why is another piece of meat different? It's just the same quarks.