De Bruyne contract will be expired at the end of this season so without having to be sold automatically De Bruyne will leave Manchester City this summer and Guardiola has confirmed that this winter Manchester City will bought some players besides those players above i think Guardiola should be buy at least 1 striker as the substutition player of Haaland because i can see it that when Haaland unable to in form Manchester City don't have any good striker and indeed they have Phil Foden but his performance is decline and last season Manchester City has Julian Alvarez but unfortunately they sell him to Atletico Madrid
I agree with you, Man City cannot continue to expect Haaland to work hard up front. We also often see how Haaland becomes unhinged when he is pressured by the opponent's defense. In addition to the decline in performance that he could experience, injury is very likely to befall Haaland if he continues to get strong pressure in every game. Getting a striker with a sharpness that is not inferior to Haaland is also very important for Man City. They have quite a lot of matches in various competitions, so it will be very important to maintain the fitness of each player to maximize the team's performance. Man City has also felt that some of their players have been injured and that makes it difficult for the game to run as they expected.
Haaland is one of the best in the world, but he is not someone who can make the team champion on his own. We can say that Manchester City has not been very successful this season, they are not playing at the top right now and they may not even be in the Champions League next season.
Haaland cannot do anything on his own, it is necessary for someone to support him. It has been almost a month since the last match he scored a goal, we cannot ignore this
Therefore I believe the problem at Man City right now is not just because of the decline in performance of one or two players. Maybe there is something bigger for them to fix shortly. If not, as you said maybe they could lose some hope in the next season.
Man City has been a very strong team in several seasons, including in the Champions League and Premier League. But that does not rule out the possibility that they will experience a big blow that can make their players' mentality fall.