The triviality argument seems to be an informal proof by contradiction.

   (1) Suppose there exists a program `conciousness.exe` whose computation is conscious. 

   (2) A block of iron is not conscious. 

   (3) There exists a (presumably time-dependent) function which maps the microscopic states of the block of iron to the states of the computation of `conciousness.exe.`

   (4) This mapping makes the block of iron is conscious.

   (5) Statement (4) is a contradiction with (1). Therefore there is no program whose computation is conscious.

I think the flaw is clearly in (4). The existence of a function decoding the state transitions of iron into `conciousness.exe` does not imply that the iron is conscious. No definition of what makes an object conscious was provided to justify such a claim.

I would say that a decoding function which maps states of the block of iron to states of `conciousness.exe` is conscious if executed (by Alice, by a computer, or in any other way). In the same way, a decoding function which mapped the states of the block of iron to states of a sieve of Eratosthenes is a prime number finder.