Yes, there's only so much information that's deeply pertinent to our lives, our interests, etc., because the complexity or breadth of those things (at least as far as we conceptualize them) is limited. I think you can ask an unlimited amount of questions, because there's no end to how obscure and detailed information can be or its contexts, but when it comes to good questions they're limited. I'm sure there are thousands of good questions, though, if you take all areas of interest and application that impact someone in some way.