Manchester City's style of play changed over a decade ago after the Arab takeover from what they were before they bought it. Because they were able to go into the transfer market and get some of the world's best players, then they won the league from Manchini to Pellegrini then to Pep. Pep came and totally improved on their style of play when he brought his philosophy of always been in possession of the ball, if you lose it, two or three players are attacking to get it back. But after the shambles of last season, yes they held on to the ball to failed in the final third and their defence. But so far in the Club World Cup, Manchester City has impressed me even though they're out, the team is like in a rebuilding phase and not so many teams in rebuilding phase can perform the way City has in the last 4 matches they've played so far.
The turning point of Manchester City's change did indeed start from their good finances after being taken over by an Arab prince. From there they could be more flexible in improving, including recruiting players who had very good quality.
Another point is when they could take advantage of something they had at that time. because without good management, even though they had money, they would never be able to play very well. Although there were several controversies, apart from all that they had good performance and good planning too.