The way I’ve been putting it over the last few years is that science fiction works by a double action. This is maybe another way of talking about the estrangement effect. Think of the glasses that you put on at a 3D movie. Those special glasses have one lens showing you one thing and the other lens showing you another thing, slightly different. And your brain puts together a 3D view from these.
So one lens of science fiction is a real attempt to imagine a possible future. The other lens is a metaphor for the way things are right now. What you get when the two coalesce is a vision of historical time, cast into the future. Like a trajectory of deep time.