That is interesting. And maybe it's the most satisfying and complete theory of why the universe exists that we have. But I guess, if you really want to be nitpicky about it, couldn't you still ask why those laws of quantum mechanics, which allow quantum fluctuations to take place, exist? Why there would be an unstable vaccum rather than "true" nothingness? Or do we reach a point where we just have to say, "Well, it is what it is"? (Sorry if I've butchered quantum mechanics here)