All the efforts to get computers to play chess mostly like humans do were made to look insufficient by a large enough neural network that took zero knowledge of human position evaluation, which just played against itself an outrageous number of games.
The plane is in many ways lesser than birds, and we barely understood aerodynamics when the wright brothers gave us a working plane: While the bird is efficient, we had a whole lot more thrust. Our planes are far better than they were back then, but not because we understand bird better, but because we focused on efficiency of the simpler designs we could build. The Formula 1 car doesn't come from deep understanding of the efficient, graceful running movements of the cheetah.
Our results in medicine have been far and ahead of our understanding of biochemistry, DNA, and in general, how the human body works. The discovery of penicilin didn't require a lot of understanding: It required luck. Ozempic and Viagra didn't come from deep understanding of the human body: Resarchers were looking for one thing, and ended up with something useful that was straight out unintended.
We might be able to build AGI with what we know of brains, we might not. But either way, it's not because we need to understand the human mind better: Do we have enough compute for a very crude systems that we know how to build to overcome our relative lack of understanding?
So if you ask me, what is the height of hubris is to think that working engineering solutions have to come from deep understanding of how nature solves the problem. The only reasonable bet, given the massive improvements in AI in the last decade, is to assume that the error bars of any prediction here are just huge. Will we get stuck, the way self-driving cars seem to have gotten stuck for a bit? Possibly. Will be go from a stochastic parrot into something better than humans, the same way that Go AIs went from pretty weak to better than any human in the blink of an eye? I'd not discount it either. I expect to be surprised either way.