He did appreciate her efforts against Pein in the War Arc. As for your next part. I would like to see the movie before I come to a conclusion that this is what really happen. Even if it did, Naruto was never obligated to returning his feelings for Hinata. I get what your saying, But the issue you are complaining about is not really that big. It was something that was not really required, but a nicer thing to do.
I did not see much of the movie so I can't say much about those two years. I will say this much, Naruto not only seems mature as a character but as a fighter to. Maybe he used those two years on more important things like training etc. Cause his fighting style really changed from using clones to a hip pop fighter. He looks like a rapper in motion when he is jingling around in his fights.
Edit: Oh can't forget those one handed Rasen-shurikens with such control.
:| I really don't see Naruto not paling around with friends. U can't really say he was in the village and zero free time. Naruto doesn't seem like that type. No doubt he trained though.
Tbh, all this situation needs is reference. Him and Hinata seem a lot closer in the movie as well. It is obvious that they have spent time together, I mean he is comfortable enough with her to invite her to his room for ramen, but it would be nice to see something that tells me he didn't take her confession and throw it on the back shelf.
Though logically thinking it's not like he could have given a positive reply since he still had feelings for Sakura
if that were the case the hesitance would make sense, but I still feel bad for Hinata
