No ones mentioning it because it isn't really applicable to the thread as presented by the OP. Theres no doubt that there was a surge of darker sci-fi that came out in the past decade. 9-11(and the wars that followed) receives alot of credit for that and thats what this thread was about. If this thread was about patriotic themes that are present in TV and sci-fi than sure. Thats not what the thread was about though
Where did I say that 9/11 didn't lead to the surge of darker sci-fi ? (like I said, the Xindi Arc was mighty dark for Trek) This thread is about whether or not we're bound for a surge of brighter sci-fi. I'm saying that when there's brighter sci-fi these days, that too is and will be different than previous brighter sci-fi as yet another consequence of the very same things that brought us darker sci-fi. Brighter could be patriotic, brighter could be hopeful, brighter could be exploratory, brighter could be enlightenment, but whatever form it takes, it is *still brighter* nonetheless.
Artistic trends tend to flow almost one way, almost like a narrative fabric. Aesthetics improve, methods are sharpened, but they're always linked as well. An upsurge in reaffirming, escapist fiction will still be tied. When I mentioned the increase of patriotism and global goodwill as an additional consequence of 9/11, it was to connect life to art, and how art will cover all bases, up to and including positive and healthy escapism.
The OP asks is it time for such fiction. I'm saying that the real question isn't about time, but how fiction continually changes and how those hopeful changes that the OP asks about are in some ways already here.