I wish Sakura had spoken up for herself. I suppose she feels down about it because it's a combination of it being Sasuke (who is the subject of many confused feelings on many levels romantic and otherwise), her being hard on herself/esteem, and the fact that what he's saying isn't wrong he's just said it in a terrible way--really dismissive, and as someone mentioned awhile back uncalled for because he's going to have to tell Naruto anyways. Whether or not she could be of use, it isn't useless answering her. What I don't like about it, is that it truly undermines Team 7 and the previous attempts at 'we'll use teamwork!'. The way Naruto defends Kakashi and Sakura with a comedic expression also demonstrates, at least to me, how sad and empty those words are. At least when he initially reacted to Sakura like that, he had a more sincere expression, but note that he didn't deny what Sasuke said.
I do believe that Sakura will prove Sasuke wrong--she has to, and I'm hoping that she finally does defend herself. Sakura doesn't have a problem speaking out against Sasuke... when it's about Naruto. I think that Sakura is still insecure about her abilities, because (quite unfairly, as usual) there is an extreme gap between herself and her teammates no matter how many times she gets her moment of determination, where she vows to show them her back or stand beside them. It must be tiring, always feeling like a burden when Sakura is so capable in her own right, and she has no advantages beyond what is in the normal range of 'potential'. Sasuke may be in the superior position, but he was born great--so was Naruto. Even Kakashi had more of a start than Sakura, and her's been 'reduced' to the same position (although, without the sharingan I think Sakura is more of an asset than he is).
So, the scene is less of an issue on Sakura because I do believe it's set up for her growth. I really doubt that will be just left like that; Sakura has to have some way of proving Sasuke wrong and gaining that confidence, how I don't know but I'm pretty positive it's happening. What bothers me about this scene is Sasuke. It has to be said, compared to how he treated Karin, he is far more rude and dismissive about Team 7 than he was with Team Taka. Maybe it's my distaste for the team which colours my perception, but if Team 7 is supposed to be so thematically important, and if we're supposed to take it seriously, the fact that Sasuke has distanced himself so much that I swear even Juugo was treated with more empathy than our main female lead, just feels really off. He doesn't have to be romantically interested in her at all, I don't want him to be, but I'd prefer if he at least showed he cared on some level, at least enough to show her some respect instead of this disdain.
I think this has written me off Sasuke's character totally. He should just go back to his team and fade from the manga after this little fight where he's needed--seriously. Sakura is far better a character to this privileged little git and his merry band of outcasts, and I wish Naruto could recognize that. Maybe if he had been consistently like this, with everyone, since his downfall it'd be more palatable since he's descended so deep into his 'darkness', but his selective favour of secondary characters just ruins that whole excuse.