Thing is, any one of Jose, Conte, Allegri, Ancelotti or even Zidane can get the current City squad to be favorites for the domestic treble and outside contenders for the CL. The most I can credit Pep is the fact that when he works with a top squad, his football is more aesthetically pleasing than the other five. But in terms of trophies, identifying players with unlimited cash, etc., it is not a big deal for any of the above managers - I don't think Pep has proven to be better than them even if he wins the quadruple this season with all the spending.
Now you realize City had a lull in their spending since Mancini. Probably didn't trust Pellegrini and were holding out for Pep. Now that he's come, they are making some massive power plays in the market.