Kurama only sucked out narutos chakra when they weren't getting along but now kurama and naruto are friends so he doesn't have to worry about that. Plus when naruto goes into kyubi mode not all of it is kyubi chakra otherwise naruto would just turn into the kyubi. So he can use wind element and use the kyubis chakra to increase his rasengan.. just like how naruto gave all of that kyubi chakra to almost everyone on the battlefield in manga 616 and even though they were using the kyubis chakra they were atill able to use that chakra for all of their own specific jutsu with the kyuni chakra just making their certain jutsu even stronger. That help out with your question at all?? So basically no, kishi did not make a mistake. He's a japanese robot and its his show so he can't make a mistake lol.
