I never even contemplated this because Kaguya was just a terrible character from her introduction but yes, she fell prey to plot, plain and simple. Her not being able to go forward, backward or down is plot. Her not being able to just push them both away with chakra fists is plot. People thinking her blindspot is big enough for a person and directly above her head are just being ridiculous and need to re-read the manga. Her not being able to just outright open a portal on either side of her and let Naruto or Sasuke fall into said portal rather than touch her, thus ruining the seal, is plot. Her showing the spacial awareness of a fodder despite having the byakugan and potentially sage sense is ridiculous and plot. Her failing to see through an academy level transformation jutsu, let alone being able to see through the clones, with the byakugan is not only plot but insulting to the reader's intelligence. Her not being able to push Naruto and Sasuke awake from her by blasting chakra from her tenketsu despite being the progenitor or the byakugan, and every other byakugan user being able to do exactly that at their most basic level is suspicious as hell and bad writing, honestly the only way she successfully used her byakugan was to aim needles. That whole fight was just a cluster of nonsensical plot and nerfing if you try to analyze it, so I think it's best to just ignore it and move on... it's almost over now. -__-