I suppose there are two approaches: 1) understand the brain in all its complexity 2) wander upon something that seems like human cognition but isn’t (i.e. GPT)
Carmack and everyone else is taking the latter approach. Carmack may end up building something that seems intelligent — if that’s what you mean by intelligence.
Consider Chomsky’s view on current AI. He may disagree with me but he certainly disagrees with the idea that actual intelligence or something like AGI will result from current efforts.
See the chapter on deep learning in this interview with Chomsky: https://m.youtube.com/watch?v=cMscNuSUy0I
If you type in AI and Chomsky into YT you’ll see many relevant interviews. The web summit one might be the most recent.
Cognitive science, mostly stemming from this common intuition, has failed us after spending decades of research effort, while minting more than a few academic careers.
Same with many once prominent public intellectuals.
GPT is certainly presenting itself to be very uncharismatic to most and humiliating to some.
Is it true, though? There is quite nice literature out there, surely John has read these papers during his bootstrap period:
https://pubmed.ncbi.nlm.nih.gov/27683554/
https://arxiv.org/abs/2203.15556v1