"Plenty of older sci-fi was pessimistic as well." Yes, but it was always a niche. Stuff from Philip K. Dick on down to J.G. Ballard was an acquired taste in it

"Plenty of older sci-fi was pessimistic as well." Yes, but it was always a niche. Stuff from Philip K. Dick on down to J.G. Ballard was an acquired taste in its day, and it was never mainstream-definitive. It was a creative and interesting counterpoint to a mainstream literature and cinema that was largely dominated by optimism. Today's mainstream is mostly pessimistic (and boringly, generically so). Pessimistic sci-fi from previous eras was bold and thought-provoking, perhaps because it was playing against the grain. And it was also very personal. Philip K. Dick wrote directly from Philip K. Dick's mind, not from some dispassionate calculation of the market's tastes. Today's pessimistic sci-fi is really just warmed-over teen romance or paint-by-numbers action/adventure with dystopian settings, a lot of it written (and selected for publication) to capitalize on a trend. "Star Trek TNG was produced before the fall of the Berlin Wall, at the height of the cold war." Yes, but TNG was created under Gene Roddenberry's watchful guidance. At least in its early run (really, up until his death), it was following the philosophical precepts he'd laid down in TOS, way back when. You could make an argument that TNG was a 1960s show, made in the 1980s and 1990s. "It's the stuff that changes the world that will be remembered, not the spoon-fed fear mongering of mainstream dystopian sci-fi drama." No argument here. I have little doubt that the dime-a-dozen dystopias of today will not be remembered in three or four decades as anything more than a market-driven fad. Truly groundbreaking works, be they optimistic or pessimistic, break the mold and establish a new one.