Kish basically gave her little to no development other than her standing up to Neji.
And even then, when you think about it, it wasn't so much meant for Hinata to develop, but for Neji to develop. Making Hinata suddenly stand up to him (solely to impress Naruto really) was really just an excuse to have Neji go full hater and nearly kill her, thus allowing Naruto to take over (the NH extremists who gush over the whole blood oath thing he does choose to forget that Naruto, as he was then, would have done the same for anyone who was treated as Hinata by Neji or anyone like him at the time, just like his explosion of rage against Pain over Hinata's "death" would have been the same if it were anyone else, from Sakura all the way down to a nameless villager) and beat Neji, allowing Hiashi to reveal the truth about his twin's death, thus changing Neji's view on things and making HIM into a better person whereas Hinata literally goes nowhere after the Chunin Exams. If anything, she regresses by the time we see her again in part two and, of course, it only worsens from there.
When I say she only cares about herself, I'm not talking about her own well-being/life/not dying. I'm referring to what she wants.
With her it's always about what she wants. Because that's who she is. A selfish girl.
And you are right, it's lazy on Kishi's part because he never cared about her. To him her character was just a plot device. Nothing more.
Yep, Hinata has had plenty of opportunities to genuinely become Naruto's friend throughout their early lives. The NH extremists will always use her "shyness" as an excuse, but the fact is that she used, or even needs, Naruto to be miserable in some way just so that he can (hopefully) overcome it with his determination and will to never give up, thus allowing Hinata to bathe in it by merely observing him and, in her mind, become stronger herself rather than actually trying to do anything herself. She just leeches off of Naruto while never doing any real work herself, which is why, if Naruto isn't standing right next to her or at least within her view, she can never do jack. So for someone who supposedly "loves" Naruto so much, Hinata was more than willing to leave him alone to suffer while taking advantage of it simply because, most likely, she was afraid of being treated like he was, and was especially quick to give up on trying to reach him (and begging Neji's freaking ghost to save him) after tripping over a measly rock, despite having some Kurama chakra left as opposed to Sakura, who not only runs out of Kurama chakra, but resorts to older, mostly non-chakra related techniques to keep him alive in any way that she knew how, never giving up on herself or Naruto.
i remember being disgusted by the naruto fanclub on narutoforums that if i said ANYTHING i'd be eaten alive but when really they made fools of themselves.
singing lion kings love tonight..PFFFT no i cannot feel it.
saying "that a boy! go get those breasts! jman would be proud!" no he wouldn't.
and being oh so very proud of his 'baby girl' more like should be ashamed of his little sh it daughter.
Yeah, even now, before I put any of my thoughts that involve criticizing The Last/Boruto/Hinata/etc. in YouTube comments or other blogs/forums, I always have to start off by immediately emphasizing (sometimes several times) that I am not a Hinata hater, Sakura lover, NS fanboy, etc. before finally putting my thoughts down and explanations why, and even then, NH/SS/pro-end extremists will still pounce and accuse me of being one of the aforementioned things and spew their usual, very few talking points.
OOOOOOOOOOOOHHH!!!!!!!!!!! 
