Hinata was always about that.
Sakura wasnt until Kage Summit arc, after that she only appeared for teases with Naruto or Sasuke and she had that little moment in the war to appease some of her fans
Now when it comes to Hinata (I hate definding her), but in Part 1 like I've always said, she had my outmost respect because I knew that there was something more behind this girl. She's got goals for the future of the Hyuga clan, and I wanna see where she goes. Then what happens.... we cut to Part 2 and I'm just like "KISHI WTF!!!" You have all the other Konoha Nakama have these timeskip development, I mean Sakura (who I was starting to have respect for after the chunin exams) all of a sudden become one of my favorite characters in the series, but Hinata reduce down to pairing fodder. Mind you this was beginning Part 2 when she first showed up and let me tell you when she fainted for the first time I just facepalmed like wow, and granted she did have her moment during the Pain arc but what happened after that the same thing occurred as when she first showed up again.
Yet when the War arc came people kept telling me You see that development Hinata has gotten in the war, and my argument is "You see how that development once again got stripped away from her."
Honestly it is so sad to see a writer like Kishi treat a character like this it is disgusting. The ending of the series is even enough to show that Kishi just doesn't care anymore.
That is particularly why now when I read One Piece, which I unknowingly dropped after Albasta since 4kids didn't dubb the arcs after that (Yes you can judge me for that but I was like 9 or 10 at the time), granted I did catch up but took a break due me being caught up with high school life. Point is I'm seeing how Oda's telling his story and it is amazing to see what how much passion has for a series that's been running for 17+ years that's impressive, and He's already got the ending of the series all mapped out in his head. That's beyond impressive actually Insanity at it's finest (but in a good way if you know what I mean).
Another series is Fairy Tail which I thought had no chance of being a great series again after the Grand Magic Games (The worst arc that made people say kitten it we out) all of a sudden The Tartarus Arc (Possibly the best arc in the series so far) came in and proved me wrong. I mean after the ending of the arc I got to see how much passion Hiro has for the series and he's even doing the spin offs, Fairy Tail Zero, Ice Trail, and Blue Mistrail at the same time as the main series (Yes the spin offs are monthly releases, but you get my point).
Finally comes Bleach, people were saying FullBringer Arc was a piece of kitten, and I can see there point. However it didn't really kill of the characters developments or their personality plus considering that Kubo said The series will end with The Thousand Year Blood War Arc I was curious. Not only that but you've got a series like Bleach, which was already falling in rankings, but do some of the most craziest kitten that occured in the beginning of the war just made me speechless. I mean when you look at Naruto's war arc in the beginning I kept telling myself when will this damn arc start blowing my mind like how Part 1 and Early Part 2 was. I mean Bleach at the start like I said before has been blowing my mind with it's war arc since the beginning and continues to do so. The chapter that came out (614) last week you can't tell me that Naruto's War had the same level as intensity (aside from a maybe 3 things taking place but that's it).
The point I'm making here is Oda, Hiro Mashima, Kubo, and Isayama (AoT mangaka) at the end of the day know what they're doing with their story and where it's going to go along with the characters. That's something Kishi will never be able to do.