We disagree on this one Justanother Hubbards claim to fame was not as a writer on diverse topics though he did write other sorts of fiction but specifically as an author of stories and novellas in the science fiction pulps especially Campbells Astounding where as you say he first published Dianetics material  Just as AE Van Vogt another Dianetics supporter or Robert Heinlein would properly be billed as science fiction writers so should Hubbard  It is clearly the one thing for which he was best known in  and it remains an important part of his career  Theres no shame in it