"How does X influence Y?" is a type we're familiar with. We call it a high concept question
The problem is underscored by your statement, "what if all of the other variables were known? What if the question-asker was so specific with every minute that there really was only one possible answer?" Such a question wouldn't be a high-concept question: but it wouldn't need to be asked, either. If the querent knew that much about the question in the first place, there wouldn't be a need to ask it.
We've always had a problem with list questions
When you sluice all the dirt away from the gold, what's left is a problem Worlbuilding has faced quite literally since the beginning. How do you ask list question on a service that is fundamentally designed to reject list questions? A list question is a question that has more than one right answer. They're asked all the time here, and we have a love-hate relationship with them. We love them because they give us a chance to express our imagination! We hate them because this service is designed to have one and only one best answer and a list question can't have a best answer somewhat by definition.
Unless you give us all the conditions, restrictions, requirements, etc. to narrow it down to just one answer.
By which time you've answered the question yourself.
As ambiguity increases, the likelihood of closure increases with it
The best rule of thumb is to avoid high concept questions. To paraphrase @Sphennings, we'll help you build your world, but we will not build your world for you. The more ambiguous the question, the more you're asking us to build your world for you.
So, what can I do?
The temptation to ask a high concept question exists because the querent hasn't had enough time in their life to acquire the education and experience necessary to answer it themselves. (Frankly, that could be said about any question, but it applies to high concept questions in spades.) We get that, but what seems to the querent like it should be a simple -enough-to-answer question is to people either or both experienced in an appropriate field or experienced in how this Stack works a massive amount of free research that should be rewarded with 90% of the royalty rights should you sell the book or make it into a movie. And that violates the Help Center's "book rule," if the question can be reasonably answered with an entire book, you're question is out of bounds.
So, whenever you're tempted to ask a high concept question, ask it first in the Sandbox, or on the Factory Floor, and get people's take on it. Because the answer you probably need is, "go research the following, then come back with a specific question."