Manchester City going to war with UEFA did not remotely feel like a surprise.
Both organisations were obviously determined in 2020 to protect their reputation, yet UEFA's decision to (try to) expel the Blues from Champions League came after years of disagreements; City fans had booed the Champions League anthem for years before the serious charges were levelled at the club, and with good reason. As much as the bad blood in 2020 worsened relations between the two big beasts, they had not been on that sound a footing to begin with.
While City are facing similar charges from the Premier League, the relationship has been very different. Given the Blues have won six league titles under the ownership of Sheikh Mansour, they have been one of the best-selling points the league have had as they have grown to accrue comfortably more financial power than any of the other European leagues.