Every era has attempted to explain the functions of the brain using metaphor, usually whatever technological apparatus most in vogue at the time. Hydraulic, mechanical, electrical, and now digital comparisons have all been made and they're all a very poor fit. You could just as easily make the same comparisons you gave to a piece of paper and a pencil. It has working memory where you write and erase lines, it has long term memory where you leave the written lines, and you can perform computations on it by writing them out long form. The comparison should seem absurd because the functions of memory and computation are not actually part of consciousness, they are things acted upon by consciousness.
This makes sense if you imaging 3 scenarios:
1) A person with no short term memory e.g. someone with acute dementia
2) No long term memory e.g. amnesia
3) No processing e.g. sensory deprivation
The third scenario is not perfect but depends entirely on how you define processing. Here I've defined it as operating on sensory input. If you want to define it as "thinking" then you will need to define what thinking is.
As for biological vs. artificial neural networks, yes it appears that a neural network is required for consciousness to exist given our single example of human consciousness. We don't know how this works so we can't even say for sure if the way we've implemented artificial neural networks would be capable of producing a form a consciousness. They can process and categorize data in ways that seem similar to what our brains do with sense perception but so far we haven't come anywhere close to simulating what we would call a conscious agent. Artificial NNs don't tie computers to the brain in a meaningful way because we are only using computers to simulate NNs. It would be better to just talk about the properties of NNs and leave computers out of it.
I apologize if I've made it seem like I'm accusing you of advocating for the illegality of psychedelics. I meant to criticize your opinion that they have little to no benefit since you were arguing that we could derive the same effects from going for a walk or moving to a different country.
"pushing frontiers forwards further and faster than space exploration" this wasn't from me and is not something I necessarily agree with