Except Kishi didn't say he approved RTN as canon and only made little to no involvement in the movie except design. More or less, RTN is like GT wheras with the boruto anime is completely different since Kishi not only oversees the anime to give his approval if it stay the true realm of his mindset but he also outline some ideas with his contribution in the writing department much like DBS. Kishi say the boruto is canon, the novel were never really much canon to begin with since he wasn't the writer. Approving something hold more weight if the author makes their involvement with the story , and just like Naruto the Last whenever Kishi disprove the way it was handled by the producer, the scripter had to keep making some readjustment to the storyline until Kishimoto was satisfied.
