Anyway, here is my point, again, since you insist: given that faith is largely belief-in-belief, it cannot be refuted experimentally.

Ok. This isn't true for everyone and isn't true for quite a few people. For example, Eliezer, myself and Dr. Manhattan are all former Orthodox Jews who (at least by our descriptions and best knowledge) left in part due to actual evidence issues. So people really do care about evidence. Moreover, most humans are pretty complicated so even if someone has some amount of belief-in-belief they often also care about evidence issues.

The simulation argument gives one model where supernatural influence may well be "real", so hard atheism fails there

I'm not sure what you mean by "hard atheism" in this context and wonder if differences in meaning are relevant here. Most atheists aren't going to claim that there's a 100% chance that there is no deity (even Richard Dawkins won't do that). So if that's what you mean then there's no disagreement. Do you mean that or do you mean something else?

Realizing that worrying about whether God is real is a waste of time lets you concentrate on more pragmatic matters, including existential risks

And if Jack Chick turns out to be correct, not only will all that effort put into existential risk be a complete waste, but you will have wasted a tremendous amount of resources that could have gone to prevent eternal torture. And this applies to less sadistic or less interventionary deities also. If you are worried about existential risk, then one is already operating on a framework that assigns a low probability to most notions of "God".

And yeah, Laplace said it better.

It may help to reread what Laplace is saying. Laplace isn't saying that he's not thinking about the hypothesis, he's saying he doesn't need it. The God-of-the-gaps created by Newton to explain planets not falling drastically out of orbit is something Laplace doesn't need. That's not at all the same thing as saying one isn't thinking about the issue.