Gaurdiola will be able to revenge their last season defeat by Real Madrid, because it will be impossible for that to happen. Next season is the last season of Gaurdiola in Manchester City and it is not possible for City to win the champios league next season because Real Madrid is still super hot with the addition of Mbappe the team will be fire.
Pep will try his best to make the competition interesting but the king will remain being king. Next season will be a tough one in UCL and apart from Real Madrid we might see surprises from small clubs that we don't expect. This is why I don't think that City will reach the finals.
You can't say things with certainty like that, because in football anything can happen, it would be better if you said "most likely" instead of "impossible". This is a prediction, and in predictions there is no guarantee that the prediction will actually happen, we should not close our eyes to things like this. Pep Guardiola also certainly understands what they will face next season, and he will do his best to make Manchester City achieve excellent results.
In general, I also agree that Real Madrid's strength looks stronger than that of Manchester City. But will that be a guarantee? On the field it will usually be much different, and it could be luck that will speak to the final result of the match. We can see from the results of the Borussia Dortmund vs Paris Saint Germain semi-final match last season. Are Bourssia Dortmund the top favourites? I said no, but they managed to win.