Hmm. I was more thinking about a physics simulation by something that is nothing like a human than an ancestor simulation like in Bostrom's original argument. I think that most people who assign a non-trivial chance to ancestor simulation would assign a non-trivial chance to physics simulation.

I don't think either variety is very similar to a zoo, but if we were in a physics simulation, I do not think our relationship with our simulators is anything like a animal-zookeeper relationship.

I also think that you should taboo the word "universe," since it implies that there is nothing containing it. Whatever it is that we are in, our simulators created all of it, and probably could interfere if they wanted to. They are unlikely to want to now, since they went so long without interfering so far.