AFAIK, we’re not really trying to build neural networks that have a similar structure to the animal/human brain.
I don’t think we need to emulate every connection, every neuron, or every circuit— but I do think the broader neuroanatomy (this region mainly processes inputs from that region, and has these feedback loops, and then mainly has outputs to this other region) is essential to emulating the way brains work.
I may very well be wrong, and I hope people in the field can forgive my insolent impression, but my impression as a biochemist/engineer is that people in the comp sci world and people in the neuroanatomy world don’t really speak the same language: one is usually bad at the other, so there isn’t really a tight transdisciplinary coupling of forces.