I have read Wiener and Ashby to reach this conclusion. I've used this argument before. A piece of software capable of creating any possible software would be infinitely complex. Also the reason I don't buy the "20 w general intelligence exists". The wattage for generally intelligent humans would be the entire energy input to the biosphere up to the evolution of humans.
Planetary biospheres show general intelligence, not individual chunks of head meat.
> Mimicking 4 billion years of evolution shouldn't take that long
Thanks for illustrating my point.
Then you can connect it up to some input and output, and ... it exhibits intelligence somehow. Initially by screaming like a baby. Then it adapts to the knowledge implicit in its input and output systems ... and that's down to the designer. If it has suction cup end effectors and a CCD image sensor array doobrie ... I guess it's going to be clumsy and bewildered. But would it be noticeably intelligent? Could it even scream like a baby, actually? I suppose our brains are pre-evolved to learn to talk. Maybe this unfortunate person would only be able to emit a static hiss. I can't decide if I think it would ever get anywhere and develop appreciable smarts or not.
> Planetary biospheres show general intelligence, not individual chunks of head meat.
https://en.wikipedia.org/wiki/Variety_(cybernetics)