Really excellent point. As a microbiologist I am of course well aware of the role that symbiosis is theorized to have played in the evolution of life of earth. No doubt it was/is an important factor. That said it was still natural selection that ultimately ‘decided’ which symbionts ‘should’ survive (if any) and which would not. I focused on natural selection because it is the ‘overarching’ evolutionary force to which all other mechanisms of evolution are subservient. It is by natural selection that any particular change in structure or function or behavior is passed on to the next generation or not. It is the ultimate ‘decider’ if you will.
As to your comment about the simulators purpose being so far outside of our limited grasp. I have some sympathy for this view and at first blush it seems patently obvious. Of course beings so powerful would have motivations and reasons that our tiny minds are simply unable to comprehend. However, the more I have thought on this one the less convinced I am of the case for it. I have been working on a piece describing why I think that but not sure when it will be ready. Hope you get a chance to read it when it is.
And thanks so much for taking the time to read and comment!