Fair, and while we can really only measure her to the others of her age as like she had 6 months of Genin stuff she is pretty much the weakest there physically and by technique variation. Except maybe Kin, and she has at least got genjutsu.
This was probably the exact kick kakashi was hoping for. Get her more motivated and willing to put effort in.
It is interesting me and my friend
@Sendicard have spent a lot of time discussing what normal progression looks like for an "Average" ninja.
(No bloodline, family techniques, clan, etc etc)
I should probably do an informational post on that as it is canon to the quest.
However, it includes the idea that you don't really teach genin many jutsu.
Meaning sakura isn't that far behind she needs physical conditioning to improve chakra capacity, and more taijutsu ability (both from skill and physical conditioning) would help her be a capable fighter without spending her limited chakra.
However her frankly insane levels of chakra control should mean learning jutsu faster in many cases a LOT faster (I'll go into why in informational post). It also means she can get away with less chakra to some extent.
None of which really fixes her core issue that most ninja focus their training on a way to hurt people and she has not yet done that leaving her without much to actively do in a more dangerous fight.
Kakashi has been working with what he has. She needs more capacity to do much of anything (except tai-jutsu but that needs training too) and he isn't the type to stand there are watch her do push ups. However Kakashi was a genius and Anbu damn young. He is pretty removed from what a normal genin should look like and even then he has two young prodigies so no one to compare Sakura to.
So I think partially he missed the fault that she was in need of more. She certainly never asked for more and her parents are ninja. He doesn't know what the standard should be for her and even if he missed it her parents should not.