Criticism, praise is a very common thing in football, all players must have felt it whether it comes from management, supporters or from other parties.
Decreasing and increasing the performance of a player is also a very natural thing, we don't always see the best game from players in every match, not just Haaland.
The role of the striker in my opinion has been misunderstood over the years, yes many people think the striker must always score goals. In fact, there are other roles that must be played, for example opening up space for teammates or other things. It doesn't have to be scoring goals, the role of helping colleagues to score goals is also a role that a striker must play.
Referring to what you said, regarding other duties as a striker, I will direct it to one of the strikers that Arsenal have. Gabriel Jesus is one of the strikers that Arsenal have, but he is not as sharp as other strikers, for example like Haaland which we are discussing. G.Jesus, is one of the important players for Arteta's squad even though he doesn't always score goals in every game. but in fact, Arteta has always played him as a main starter. because, G.Jesus has other advantages, he is able to play adaptively, find gaps in empty space, make quick transitions, and he always rotates with his teammates. not infrequently, G.Jesus opens up space for his teammates to create opportunities. that is why, Arteta has more trust and always makes him a major player.
Speaking of Haaland, this player is a goal monster. proven, he became the top scorer in both the domestic league and in the Champions league last season. even though in 2 crucial matches, Haaland did not contribute in terms of scoring goals, but he had opportunities that almost found the opposing team's goal, except for the match against Sevilla. Haaland's performance did not look so impressive, it is very natural because City did not play with their main full star. plus, it looks like Haaland is marked very tightly. overall, i agree with what you said. that criticism and praise are commonplace, as well as the ups and downs of the players' performance. next, when City play with their main squad. no matter which team he plays against, Haaland will always be heavily marked.