Yes, it's true that modelling just a single cell's interactions with its environments is beyond our capacity.
But here we're talking about simulating how a brain reacts to signals at a higher level of abstraction: we're studying an "emergent" phenomenon. We don't need to model molecular interactions, and we absolutely can model this using artificial neural networks.
This doesn't mean we'll be able to completely accurately model its behaviour, but we should get a lot closer than many HN commenters seem to believe. Biological neurons don't have magical properties, they just have more side-effects.
> we're studying an "emergent" phenomenon
It's like saying that mapping all cells in human organism to addresses in memory will give us emergent human inside computer.
But still at abstract layer we just do not have a model of a working brain, we only have maps of neurons, not an actual "algorithm" or a model of all relevant environment interactions needed for a working brain or a set of "abstract instructions" needed for it to work. I think you are over optimistic about current state of our knowledge if we can't even model organism with few thousand neurons accurately. Imagine trying to do that for tens of billions of neurons and trillions of synapses, especially that we know brain doesn't work like an ANN at all[1].
Sounds more like they're saying: a knee is a knee, it doesn't have any magical properties. Build something that bends, and it will behave like a knee. I don't know how true that is, obviously.
If you're active, knee implants have to be replaced after 15-20 years, because they detach from the bone. Knee implants can harbor pockets of infections because they don't have an immune system. They are also more prone to dislocations.
They are objectively inferior to a healthy organic knee.
But most of the reasons why artificial knees are not as good as the real deal have to do with the fact that they're made of inert (albeit fancy) materials. They don't have the ability to continually heal and do tissue remodelling, which is what real tissue does.
I feel very optimistic when I think about this: we're limited, but I think it's absolutely wonderful what we're able to do.
Hope that reality isn't 50-years or more into the distant future.
I'm sorry, I'm not quite sure how your profession is relevant to this discussion. Are you a biochemist who studies neurons and the ability to simulate them? That would be relevant.
I can think of at least 4 other broad specialties that would be more relevant to the discussion: neuroscientist, computational biologist, neurologist, computer scientist who specializes in simulations of biological systems, etc.
So was the first line just a reaching appeal to authority? If not, in my opinion you should include more context about how your experience is relevant in the future.