Most good science fiction is about social futures. If you think, say, the Culture series is about aliens, giant spaceships and laser battles, then you really haven't been paying attention.
Yes, one story I read long ago sticks in my mind. It was about a society where the lower orders were obliged to consume and meet targets in consuming. The higher up the social order you went the less you were obliged to consume and the simpler and less onerous your life became. It probably seemed quite fantastical when first published.
That is probably Fred Pohl's 'Wizards of Pung's Corners" or 'The Man Who Ate the World"
A few responses.
PD James, yup. I posted that on the fly, but regardless of the lack or a war in the Aldiss, it was the concept that James nicked and it was the concept she was praised for.
Fans (a word invented by and for SF fans, BTW) avoid the term sci-fi. The preferred term is SF, sci-fi being reserved for silliness like Star Wars. All SF fits the term 'speculative fiction', as the basic root of SF is to say "what if?" and imagine what effect a single change would have on society. That change could be an alien invasion, it could be worldwide sterility. It could be a resurgence of religion (a lot of SF about that) or about a change in politics. The key is that examination of the results rather than obsession with the events, which tends to relate more to sci-fi than SF. As an example, a large proportion of Phil Dick's work is about what it means to be human. Starship Troopers is a book about the meaning of adulthood and personal responsibility, and I saw a complaint from a reader that the book didn't have enough battle scenes in it. The Verhoeven film was sci-fi, as all it contained was flash and bang. Fans hate it.
Atwood's refusal to accept what her work is comes from simple snobbery, and it doesn't matter where the snobbery emanates from. It is the same attitude inherent in "U and Non-U"
As an aside, the SF writers 'trade union', SF Writers of America, which I believe Fred Pohl was very involved in, heard that Lucas was suing Battlestar G's makers for plagiarising Star Wars and so rang him to ask how the lawsuit was progressing.
"Why do you ask?"
"Because if you win, we'll sue you"