It's not hard to see that the reason NN are becoming the prime candidate for AGI, is because of their inspired architecture based on biological neurons. We are the only known AGI, therefore something similar to the brain will be producing an AGI. NN at least mimic the massively parallel property of biological neurons. And if we're optimistic, the fact that NN is mimicking how vision works in our brain, might mean that we are at some point in the continuum of the evolution of brains, and it's a matter of time until we discover the other ways brains evolved intelligence.
What keeps me optimistic is evolution. At some point brains were stupid, and then they definitely evolved AGI. The question is how did this happen and whether or not there is a shortcut, like inventing the wheel for transportation instead of arms and legs.