Haaland is a pure poacher where he has good ball control and finishing but on the other hand when he becomes a pure poacher then indirectly this needs someone who can flow the ball for him because Haaland's style is not a type of picking up the ball and dribbling like Mbappe but he prefers to find a good position and wait for the ball to finish with accuracy and good body balance.
When the midfielders can't flow the ball well then this will be a problem for Haaland because he becomes closed and confused when the ball is not flowing well so this has an impact now when Manchester City lost several players like KDB and Rodri he became stuck and had difficulty gaining momentum.
I like the word "confused" you made use of and to me it fits most of his performance as of late. I feel he could need a little time out from the starting line ups, maybe he should be started from the bench because if you notice, eyes are still on him even when they know he's not the only threat bit for now, he has the most deadliest finishes. No doubt that Jullian is good but I feel the Spaniard just came into the scene not too long ago and even when Foden runs with the ball, all what most defenders have at the back of their minds is "stop that Norwegian giant from getting ahold of the ball" because chances of passing to him are likely.
There is nothing to say because indeed with his condition in the last few matches when he did not get a really decent supply of balls he did look confused because he was tightly guarded, on the other hand he also could not develop his game because he could not pick up the ball to the middle of the field and dribble because Haaland's focus in the match was only as a targetman and waited for a pass that could be maximized for a goal.
Making him a reserve even with the excuse of a temporary break from the line up I don't think it can be done because however Manchester City still really needs him, it's just that what must be addressed is their midfield in order to fill the void left by Rodri and KDB.