After all this time, I'm shocked that this Itachi hype still lives.
It is was crystal clear that Kabuto was leaps and bounds above Itachi. There is no changing that. Itachi can't actually harm Kabuto, which clearly isn't the same the other way around.
Itachi, not being an Edo Tensei, lacks his infinite stamina and is stuck with his inferior counterpart (2.5 out of 5, was it?). Itachi's not going to be able to freely use jutsu due to his low chakra capacity; you can't say the same for Kabuto.
Itachi's only saving grace is the final form of his Susanoo, even then it is debatable if he can do much. I won't comment further, because regarding this debate, it should be clear that Itachi needed Sasuke to hold his own the way he was. For example, what happened when Kabuto started using the Sound 4?