Uh, no, science fiction can be set in the present, or even in the past.
I find myself thinking of the literary snobs who differentiate contemporary realism from genre fiction (and look down their pointy little noses at the latter). All fiction is genre fiction; contemporary realism is a genre in itsef (and so is historical realism). In bad fiction, the story is the slave of the genre. In good fiction, the genre serves the story (and, seemingly paradoxically, is in turn far better served by the story than it could ever be by a story that is its slave).