I understand that some like to pretend though, and pretend that IPU is a devestating argument. Of course, it falls on its face because we know everything about it.
Actually, it is a very effective way of showing the absurdity of arguments such as "you can't prove XYZ isn't true", the old trick of demanding that skeptics disprove claims instead of the claimant providing evidence.
The IPU device shows that any absurd claim can be made. Proving it true is the burden of the claimant. The skeptic doesn't have to disprove anything.
In the classic form, the arguments follow these lines:
Claimaint: "Psychic Joe hears messages from the dead and you skeptics can't prove that he doesn't!" (Argument: you can't prove it isn't so, therefore it's so)
Skeptic: "Well, you can't prove that I don't have an Invisible Pink Unicorn in my garage, but that doesn't mean I have an Invisible Pink Unicorn in my garage."
Claimant: "LOL, everybody knows there's no such thing as Invisible Pink Unicorns!"
We can't prove there isn't a God. Similarly, we can't prove there aren't Invisible Pink Unicorns or Flying Spaghetti Monsters. Common sense tells us that there aren't, but if our basic claim is that anything is possible, well, then anything is possible.
IPU is often used to try to illustrate a simple logical concept to the willfully ignorant. If it fails, it is usually due to sheer obstinancy on the part of the willfully ignorant, not because the underlying argument is weak.
To take a real-life example, we can't prove that there aren't sea serpents in San Francisco Bay, but that doesn't make the pixelated video that has been offered as evidence into anything resembling evidence, let alone proof.