A neuromorphic AI could be constructed without understanding how the brain actually works. You could run that faster, but even with a billion years subjective

A neuromorphic AI could be constructed without understanding how the brain actually works. You could run that faster, but even with a billion years subjective you still might not be able to come up with ways to improve your own mind if you aren't smart enough in the first place. Of course, the intelligence threshold for self-improvement is lower if your mind is simpler...but the clearest (and fastest?) route to something you could reasonably call AGI may be dumbly reimplementing a human brain.