> No you don't understand how a neuron works fully or else you'd be able to make a synthetic one from chemical building blocks not using another living thing to do it.

This is a bizarre contention. The test for whether something is understood isn't that we have the engineering capability to replicate it.

Just because you partially understand something like the ancient farmer partially understands plants by knowing to plant seeds, that doesn't mean you fully understand it and can thus reproduce all the properties of it synthetically like you are trying to reproduce a brain synthetically from scratch inside a computer with LLMs.

You can reproduce part of it, the intelligence, but consciousness and intelligence are not necessarily the same thing. This is why I compare it to cargo-culting. The Melanesian tribesmen thinks the coconut looks like a microphone, and he can use it as a paperweight just like a microphone and that's useful, but it is not actually a microphone.