For me, Man City is still the favorite to win the EPL title, because Man City is only 5 points behind Arsenal who are in first place and the EPL league is still very long, not even half a season yet. You need to look at last season, before the middle of the season, Man City was also behind by a fairly large difference in points with Arsenal, but entering the 30th EPL League match, Man City was slowly able to catch up with Asenal in points to reach the top of the standings. At the end of the season, Man City became champions. Here are the facts
Regarding KDB and Hallaand, I read news that it is possible that in mid-January they will be included in the squad again. But what I want to say is don't think that Man City is unable to catch Arsenal because they are now in fourth position. Learn from history, they have a strong mentality, especially as coach Pep Guardiola can return to first place at any time.
Manchester City might have been dominating the EPL since the arrival of Pep Guardiola, however im not quite sure if they'll still win the league again this season, if you notice their performance in the league currently you'll see they've declined and are now finding it tough winning against some mediocre teams in the league, therefore it made them drop points that’s why they're in the position they're currently, well i get your point and there's a possibility of history repeating itself but im not going to conclude yet till they get to the 30th week.
Since Kelvin Debruyne absence alot has happened and it felt like some part of the team became exposed, giving other teams a chance to predict Guardiola's strategy, but with his arrival by January, we'll begin to see a very tough and brilliant City that scores alot of goals, it's going to be a big boost for them cause Haaland and Debruyne understands eachother very well.
Manchester City has faced challenges and dropped points against teams they might have been expected to beat, But that's is popular in Premier League where a favorite team being beaten by mediocre team, and that can't be a reason to judge a team having a declining form. It's not uncommon for top teams to face difficulties and drop points in the course of a long season. I think it's just a temporary setback that is experienced by any team rather than a sign of a long-term decline.
The absence of Kevin De Bruyne undoubtedly has a significant impact on the team's performance. His return in January could indeed bring about a positive change. De Bruyne is a world-class midfielder with the ability to influence the game both defensively and offensively. His understanding with new signings, like Erling Haaland, could provide the team with the spark it needs to regain dominance. Pep Guardiola is a manager with a track record of success who has the tactical acumen to adapt to challenges and find solutions. The team's performance in the later stages of the season, especially after De Bruyne's return, might demonstrate their ability to overcome early-season struggles.