Indeed I have no understanding of whether the material universe always existed or, if not, where it came from. (Maybe some physicists have a good idea; I don’t.) Insofar as saying “God did it” is just a fancy way of saying “I have no clue how the universe appeared,” it’s an extra hypothesis that doesn’t explain or solve anything, because then you’ve committed to saying that everything needs a creator, which means you need an infinite regress of “Who created God?” And the notion of Creationism still doesn’t explain how or why the universe was created or what it means. For most people (non-physicists who really don’t know), the best answer is just “I don’t know how the universe got here.” That’s a non-theist answer. Theism adds no information in this specific department. As such, at least in this area, theism is a smokescreen for our own ignorance, and it’s the wrong answer to the question.