> One of the questions should be: Why should we build a model for the world?
The decision not to build a model, is a model.
> Is that really possible/doable?
Models are just data-driven predictions based on understanding. The better the data, the better the understanding, the better the model.
If a model for the world is impossible, then either the data is impossible to gather or process, or the understanding is impossible to achieve.
Data is just facts based on observed events, so I refuse to believe that a model for the world is impossible based on ability to track data.
Understanding is the wildcard - humans are complex beings. But each tiny step forward increases global understanding. Years ago, autism was considered "cold mother syndrome". Now through decades of careful and detailed analysis it's understood as a neurological disorder. Depression and anxiety were thought to be issues of the soul, demonic possession, laziness, etc. Now there is an ever expanding array of diagnostic tools to help sufferers.
So I refuse to believe that understanding is impossible.
tl;dr: Yes, a model for the world is possible.
> And if the real answer is "no",
That's a big if.
> why should we apply that failed model to the real world
"failed model" what failed model?
Also recall doing nothing is also a model. Bring on the dark ages!
> affecting (potentially in a negative way) the lives of millions of people?
In my world view, doing nothing and praying to higher powers, or allowing chaotic despots to rampage the lands has already caused immeasurable premature death and suffering.
Why would anyone vouch for a return to the dark ages, just because progress feels like effort?