Upvoted, but one quibble:

If you, say, claim that "Time didn't exist before the Big Bang" is a complete and satisfactory solution to the problem "Why does something exist instead of nothing?", rather than (as is the correct answer) trying to explain why saying "God" (a) doesn't help and (b) constitutes the cardinal sin of Just Making Stuff Up, then you have lost all claim to any moral victory.

The point of that sort of argument, in my view, is not to propose a satisfactory solution, but to demonstrate why the question isn't meaningful. When a person asks a question like "What caused the universe?", ey is assuming that the universe needs a cause. However, causality is a property of events within a time-ordered system, and the universe is such a system, rather than being within the system. Time and space are unified, so considering them separately (which is what the question does) is erroneous.

This is similar for questions like "why is there something rather than nothing?". Implicit in the question is the possibility that there could have been nothing, and that's wholly unsupported by observation; even the vacuum is full of virtual particles. We may think that we can imagine that possibility, but that doesn't make it viable. That kind of question is never going to have a satisfactory answer, because the underlying premise is faulty.

I agree that it's important to point out how "God" isn't a good answer to those questions, but I think it's more important to point out the flawed thinking which leads to asking the questions in the first place.