The article is super focused on the hardware side of things, and to a point, that makes sense. Your hardware has to be able to handle what you're simulating.
But it's not the hardware that's the difficult problem. We're nowhere close to hitting the limits of scaling hardware capability, and every time people declare that we are, they're proven wrong in just a few years, and sometimes even in just a few months.
It's the software. And we're so far away from being able to construct anything that could think like a human being that the beginning of it isn't even in sight.
LLMs are fantastic, but they're not a path to building something more intelligent than a human being, "Superintelligence". I would have a negative amount of surprise if LLMs are an evolutionary dead end as far as building superintelligence goes.
Is modeling neuron interactions the only way to achieve it? No idea. But even doing that for the number of neurons in a human brain is currently in fantasy land and most likely will be for at least a few decades, if not longer.
If I had to characterize the current state of things, we're like Leonardo Da Vinci and his aerial screw. We know what a helicopter could be and have ideas about how it could work, but the supporting things required to make it happen are a long, long way off.