Non-simulated beings cannot use them to predict the universe’s future or hypothetical universes’ states without waiting a significant amount of time, comparable to the system itself reaching that state if not much longer. Thereby, such beings will less likely be tempted to create simulated universes...
You’ve done an impressive job of clearly and succinctly explaining the simulation hypothesis, the significance of sim blockers, and the concept of computational irreducibility. I agree with your premise that computational irreducibility makes it harder to use simulations to predict the future, and therefore may result in fewer simulations being created. However, that is only true for simulations that attempt to predict what will happen starting with where things actually are right now.
One useful application of simulations is determining what would happen if a particular set of circumstances should occur in the future. For example, what would happen if there was a sudden worldwide outbreak of a highly contagious virus, or what would happen if a celebrity with no political experience or qualifications were elected president of the United States.
If the starting point of the simulation differs from the present configuration of the universe, it doesn’t matter whether or not the simulation can compute the state of the universe faster than the universe itself reaches that state— because the simulation and the universe are at different starting points. The predictive usefulness of such a counterfactual simulation would depend on the possibility that the real universe may, at some point in the future, approximate the starting point of the simulation.
This sort of simulation could be quite useful so there could be many of them. However, this doesn’t challenge your core premise. Simulations will still be less popular than they would be if they could predict where the universe is going to go FROM HERE faster than it actually does.
I really liked this extended passage on math circles from John Psmith’s REVIEW: Math from Three to Seven, by Alexander Zvonkin, it made me wish math circles existed in my home country when I was younger:
You can start math circles really really young:
(Sadly I only learned of the existence of math circles well after graduation, a few years ago when I used to spend more time on Quora and noticed that Alon Amit, the most respected writer on math topics and someone who’d done many interesting things in his life, described himself simply as a “mathcircler”.)