[derektank]

There are alternatives and I was perhaps too quick to assume everyone agreed it's an emergent property. But the only real alternatives I've encountered are (a) panpsychism: which holds that all matter is actually conscious and that asking, "what is it like to be a rock?" in the vein of Nagel is a sensical question and (b) the transmission theory of consciousness: which holds that brains are merely receivers of consciousness which emanates from other source.

The latter is not particularly parsimonious and the former I think is in some ways compelling, but I didn't mention it because if it's true then the computers AI run on are already conscious and it's a moot point.

[Davidzheng]

I do think "what's it like to be a rock" is a sensible question almost regardless of the definition. I guess in the emergent view the answer is "not much". But anyhow this view (a) also allows for us to reconcile consciousness of an agent with the fact that the agent itself is somewhat an abstraction. Like one could ask, is a cell conscious & is the entirety of the human race conscious at different abstraction scales. Which I think are serious questions (as also for the stock market and for a video game AI). The explanation (b) doesn't seem to actually explain much as you state so I don't think it's even acceptable in format as a complete answer (which may not exist but still)