1. There are lot of people whose Thing is consciously, deliberately, thoughtfully writing sociology, politics, economics into their stories. For my part, although I have my opinions on issues, I feel no delight or urgency in consciously expounding on those issues in my fiction. And some days I want nothing more than a vacuum for my story to exist within. However, on this topic I defer to Italo Calvino, who a) is more eloquent than I am, b) surely wrote stories fantastic enough to know. In his Invisible Cities, Marco Polo describes "a great number of lands" to Kublai Khan, until:
“Tell me another city”, Kublai insisted. [...]
“Sire, now I have told you about all the cities I know.”
“There is still one of which you never speak.”
Marco Polo bowed his head.
“Venice,” the Khan said.
Marco smiled. “What else do you believe I have been talking to you about?”
The emperor did not turn a hair. “And yet I have never heard you mention that name.”
And Polo said: “Every time I describe a city I am saying something about Venice.”
“When I ask you about other cities, I want to hear about them. And about Venice, when I ask you about Venice.”
“To distinguish the other cities, I must speak of a first city that remains implicit. For me it is Venice.”
2. I don't mean, actually, that in writing a story I must be saying anything about this particular universe that you and I share. But I cannot help saying something about the world that I created. Even if something is merely for a laugh, the fact that I think it is worth a laugh, or the fact that some reader thinks it is worth a laugh, means that there is something entertaining in that setup, in that situation, in that world. Therefore, the author has said something about that world, not to mention themselves, after all. And the bigger the world, the more is said. The only way to say nothing, to preserve that vacuum, is to remain silent. To not create at all.
(3. ... isn't the author dead anyway? So who cares what I intended ... )