I agree that Man City have spent a lot but if they have filled the gaps that needed filling and have bought good young players as well as top quality experience.
This is what makes Man City, Chelsea and Man U the best teams in the PL, and PSG, Bayern Munich, Barcelona and Real Madrid the best teams in their leagues.
I’m not sure every top manager could do just as well with the same players.
Mourinho, for instance, plays a different style of football to Guardiola which is far more defensive even though it is effective.
If you spend big on the best players, that fit in the system you play, then as long as the system works then you will be challenging for the title.
If you have inferior players, played out of position, in a system that they don’t know how to play, you are not going to win much and are going to end up like us.