I look at it as trying to break the speed of light. Even at 99.99%, almost infinite energy and mass of whatever is trying to get to that speed.
for such a device, it would have to have the power of the sun to draw on and storage and process would require something as large to exist on as the world it was trying to sim....IMHO.
To take in and process every variable to me is impossible. Not to mention the amount of programmers required to make the damned thing work.
When it becomes a part of the ecosystem it has to simulate itself simulating itself simulating itself simulating itself…
You cannot prove the outcome. This is Godels theorem in a nutshell.