This character is one of those who most needed to develop a much more dignified introduction than the one they gave him. Starting with the fact that her first and only appearance is right after the pathetic death of the great Madara, it takes away a lot of weight from her as the ultimate villain. I mean, in comparison, Madara had an excellent development long before his appearance, there were entire chapters that developed or told something about this character, which helped give us an idea of what he was like and that ultimately, Madara would be the best villain in history.
Even his actual appearance on the battlefield of the Fourth Ninja War was one of the best chapters that Shippuden has of this much criticized arc. Anyway, I think that if the creator had given her an introduction or a better development, with details or direct and indirect signs of Kaguya and her presence during the story, before her appearance, maybe, just maybe would have been better. But it is clear that at that end the creator was already tired and had no ideas of what else to do, so he did the first thing that came to mind and it turned out so badly done, honestly.
It's not that I'm saying I don't like the character, but Kaguya had a lot of potential to give her more development or presence like Madara himself had or even more taking into account the weight. of its existence in history. And then, in the horrible sequel they released for Boruto, one or another villain appears who is related to Kaguya or something like that, which gives me more reason that she deserved a better development at the end of Shippuden.
But hey, I think if they had left Madara as the final villain it wouldn't have been so bad.
Just my opinion.
Nice post.