It all depends upon the limits in which one defines the scope of the fiction's divorce from science fact. The fantasic elements of Star Wars is understood in terms of technology rather than supernatural terms and, in that, is a scientific adaptation of fantasy and fantasy is fiction.
In all, I really think it's unnessecarily pedantic to give a shit. Also to define science fiction in terms of scientific progress will undermine it as a literary genre as you keep punting its pioneers into fantasy.
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