The simulation argument is quite popular these days; Elon Musk famously finds it compelling. I don't, but for those who do, I think it has an important consequence that is obvious yet underappreciated: if we live in a simulation, then a form of theism is true. If the simulation argument is valid, then atheism is improbable.
The agent responsible for the simulation would be the God of our universe: it intentionally designed, created and sustains our universe for some purpose. (That purpose might have nothing to do with us or our pocket of the universe, but since life on Earth is the most complicated system we have observed so far, we can at least take as a working hypothesis that the purpose is connected to us.) This already implies we have at least a God of classical deism.
Furthermore, if we can use our simulations as an analogy, we should assume the simulating agent has ongoing access to the substrate running the simulation and the ability to modify its state. In other words, the agent is likely to be omnipotent (in our universe) and miracles are possible. (This is not the "can make a rock so heavy he can't lift it" straw-man omnipotence targeted by many atheists, but it's well within Biblical parameters.) It's also possible for the agent to reveal itself to us, and that it might want to.
The other two "omnis" do not seem to follow. I see no reason to believe that the simulating agent would be omniscient, even just about our universe. Likewise I see no reason to believe it would be omnibenevolent. However, being omnipotent, it could make us believe it was omniscient and omnibenevolent if it wanted to.
I don't expect to see proponents of the simulation argument in churches en masse anytime soon :-). However, they should be taking theism seriously and atheism not seriously at all.