The simulation argument really does seen to be the goddidit argument updated for the digital age.
For example, many religious believers, including especially evangelicals I think, believe that God created human intelligence on only one planet, earth. So why is the universe so vast yet absent of other intelligent life forms? Because — and I have actually seen an entire philosophical paper devoted to to this claim — God wanted to show us his love for us so much, that he created an utterly barren universe, except for earth, just to show how special he thought we were. This is the supernatural equivalent of the “CPU-intensive” simulation argument.
God created us, but who created God? Simulators created us, but who created, or simulated, the simulators? Same question in different contexts. Is it Gods all the way down? Simulators all the way down? The arguments are parallel and both avoid the idea that reality is what it is, no Gods or simulators required.
Or take the so-called fine-tuning argument. It basically holds something similar to what follows:
1. Several important constants of nature must be what they are, or very close to what they are, to make it possible for carbon-based life forms to exist.
2. Carbon-based life forms exist.
Therefore:
3. The universe as we find it is highly improbably, OR, put another way, it cries out for explanation.
4. The best explanation is that the universe was created by some intelligent agent — either God, or intelligent agents running simulations on super computers.
Therefore:
The universe was created by some intelligence, either God or intelligent agents running simulations on super computers.
Another way to put it night be:
Given that the universe is highly improbably life-friendly, it is more probable that it was designed this way than that it is this way by accident. The designers may be God, or intelligent agents running simulations on super computers.
The problem is that this argument seems no good, because I don’t think that 3 follows from 1 and 2.
That is, even if we grant premise 1, that the constants of nature must be identical or very close to what they are in order for carbon-based life (or any conceivable life?) to arise, it simply does not follow that these constants are improbable. For one thing, they are the only constants we know about, because, well, they are constant. There is no probability distribution here. There is no way of even knowing whether these constants could have been different.
The idea is sometimes cashed out as follows: It is logically possible that the constants could have been different, and the ways that they could have been different are practically infinite. But in that case the probability of any ensemble of constants manifesting themselves is not only staggeringly low, but effectively zero. Moreover, logical possibility is not the same thing as physical possibility.
A multiverse along with God or the simulation argument is sometimes evoked to explain fine tuning. But to me none of these are necessary, because the whole fine-tuning argument founders on a misapplication of probability. So the fine-tuning argument for God, a multiverse or the simulation hypothesis cannot even get off the ground. There is nothing to explain. Like God and the multiverse, the simulation argument explains nothing about the reality that we find ourselves in, so far as I can see. They are all superfluous and cleaved away by the famed razor.