It's not. Indeed, "predictive accuracy" on simulated data is largely a meaningless metric in any case. The simulation's set up determines the predictive accura

It's not. Indeed, "predictive accuracy" on simulated data is largely a meaningless metric in any case. The simulation's set up determines the predictive accuracy of any model of it. The only value of this metric, post-simulation, is to determine whether or not an experiment is worth the ROI -- ie., it's essentially a way of determining whether some set of premises (simulated) are possibly consistent with a given predictive project.