İlkay, De Bruyne, Haaland and Bernardo were on the bench in this match. However, they still managed to beat Chelsea and dominate the game. No doubt they have set the bar very high. We can say that they are the best team in the world right now. They did not even give the ball to their opponents in the champions league semi-final match they played with Real Madrid. They're like Barcelona with Prime Messi. Undoubtedly, they will be the best team in the world for a long time. I can't say anything about Chelsea. They need players who can take on the role of the leading player in the team. I don't know if Neymar can do this job, but there were reports that they wanted to transfer him for a while.
There's no way you can compare the now Chelsea team with the current Manchester City's squad even in the absence of those players you made mention De Bruyne, Haaland and Bernardo. Guardiola has build up the Manchester City team to a world class level, which every team out there will find them difficult to defeat, even at the European level.