Yes, and CFD simulations notoriously break down the moment you scale them up. Look at weather forecasting! Extremely complex models that push the boundaries of modern computational capabilities, and yet we are barely able to forecast weather a day or two out. Sure, we can make vague forecasts over large areas, but errors compound and we lose both granularity and accuracy.
And that's with us having a pretty solid understanding of how fluid dynamics works. We have an extremely poor understanding of how a brain works, doubly something of the complexity of the human brain. We are fundamentally unable to study it during operation, because we don't have a non-invasive high resolution access to it's internals. We are basically butchers sticking electrodes into living tissue.
The article itself proposes that we may - barely - be able to study the workings of the brain of an extremely simple organism.
A rocketry analogy would be Archimedes dreaming about people traveling to the stars.