I am not sure I understand how is that important or helpful. In simulations of physical systems, there already is a barrier of what we can do (chaotic behavior

I am not sure I understand how is that important or helpful. In simulations of physical systems, there already is a barrier of what we can do (chaotic behavior) regardless whether or not the underlying physics is deterministic or not. In other words, even if the question ("is universe deterministic") remains unanswered, we can already simulate all we need to the way it's possible to do it.