Except that they have been deemed not canonical by decree of the Supermanica overlords, a higher power beyond appeal to such human concepts as logic, etc.
Not to mention, less than 1/100th of the current canonical texts have been referenced in entries in Supermanica. Including another entire 30-year series seems a little like getting ahead of ourselves. We have a lot of work ahead just to fill in the post-Fleisher work as well as the series he didn't cover (Lois, Jimmy, etc).