Margaret Atwood did not win the Booker Prize for Oryx and Crake and sequels, the "arguably SF" ones mentioned above, but for other novels. IDK if "The Testaments" qualifies though.
This might make MJH the first Sci-Fi author to win a Booker prize for a Sci-Fi novel.
> IDK if "The Testaments" qualifies though
I would have a hard time countenancing an argument that The Handmaids Tale (and by extension, The Testaments) is not sci-fi, in a world where Heinlein's "If This Goes On—" is widely regarded to be sci-fi.
On the other hand, if Atwood doesn't wish to be regarded as a sci-fi author, so be it