Honestly, I can't say I know. The only way it even slightly makes sense is that he was rebelling against outside forces for possibly forcing him to write the ending the way it was. That cold be the explanation for all the mistakes, the terrible interviews, the retconning, and everything else. It could be his own way of rebelling by trying to discredit the ending. Deluded SS shippers continue to spout that nonsense that Sasuke was pushing Sakura away purposely and was trying to hide his feelings, but how do you hide what you never had?
It's possible that Kishi wrote it like that for the purpose of making it unbelievable, as he did with turning Naruto into scum, Sakura into a shallow hypocrite (i.e. her feelings being borne of a rivalry, yet that is acceptable for her), turning Hinata into the main character, etc. Either that, or he's an idiot.
Yes, I've wondered about this too, that maybe Kishimoto lost his enthusiasm for the series after his editors/SP chose Hinata as the central character over Sasuke. Kishimoto loooooved Sasuke, and the story really revolved around the Uchihas. But the anime was about the Hyuugas, and in the end Neji and Hinata were the important ones. Not Sasuke.
I wonder if he just realized he'd lost the tug of war between the manga and anime, and he just washed his hands of it? Did what he needed to do to end it quick? Cause like I said, Sasuke really got the shaft too in the end. He wasn't even in the movie! (well, for half a second or so) Since when has that ever happened? Hinata is now the primary character, and Sasuke is now the forgettable character she was.
Sakura is actually a very bad match for Sasuke since Sasuke is a boy who lost everything and was forced to become an adult at a young age while Sakura is a girl who had everything and was too naive to know it. Sasuke might end up resenting Sakura for having parents and not understanding him. She can't understand him because her family was not killed by the older brother she admired. Sasuke's one true love will always be his family and it makes me shake my head when deluded naive SS fangirls think Sakura can replace that.
Yes, you'r right, Sasuke is not a good match for her. I've thought that too, that Sasuke's only real love was for his family. And when they died, it died with them. I could more easily see him getting with Karin, who represents adulthood and sex and no commitment, over Sakura, who represents the village and commitment and a family. As much as he talked about rebuilding his clan, I don't think that was ever a reality for him. Cleansing the Uchiha name, yes. But never starting another family. And that's probably why he's now out the door. Because Sakura and sasuke don't make sense together.
Plus she didn't understand people very well, considering she always took what Sasuke said at face value because of his being the best, and always looked down on Naruto, thinking as if she knew him best, but she was so wrong since she knew NOTHING regarding Sasuke after so long, yet got to be more understanding toward Naruto, which is what pisses me off about the ending, that all that got thrown to the wind!
Yes, Sakura's character evolved. Out of the whole manga, only her's and Naruto's did. Hinata's didn't, no matter what her fans or shippers will say. She was still hyper focused on Naruto, even as her cousin's body was going cold at her feet. It's awful. Just really makes me think that Kishimoto gave up.