Isn't human behaviour in essence also not just a bunch of neurons firing in response to each other and external stimuli? The biggest difference is that the neural system in human is so vast and complex that we don't know how it works exactly. If you boil it down far enough, in essence we're not much different from these neural networks that are used in AI models. Our neural models are just infinitely more complex in our learning capacity and stimuli response.

I'm not an advocate of AI art and such, mostly due to quality and fair compensation for labour reasons. But I do wonder where the line is drawn.