Manchester City and Real Madrid have always been able to dominate their opponents so far, but you should not exclude Bayern Munich. This season, Bayern Munich is starting to perform better compared to last season, since Kane presence in the squad, Bayern Munich has found it easier to win. Real Madrid is always the favorite because of its status as the team that has won the most UCL trophies, but I still doubt Real Madrid quality this season. I'm still waiting for the moment of Real Madrid versus other big teams to draw conclusions, while Manchester City is no longer in doubt, let alone its status as defending champion.
I will not have complete support or confidence in any team that is displaying more potential to win the Champions League this season yet. I'll wait until the quarterfinals to make a final decision on which club has a better chance of winning the title. At that point, most of the low quality teams would have been eliminated, leaving just the big teams to select who would progress to the next level of the competition, which would be fiercer at that point. At the moment, Bayern Munich, Real Madrid, and Manchester City are the most talked about teams to win the trophy, but I believe more teams can still stand any of these teams before we can finally conclude about them.