Here are the winning chance of each team to become a champion in the next season:
60% for Real Madrid
39% for Manchester City
1% for Arsenal, Inter, Milan, Barcelona, PSG, Bayern Munich, Leverkusen etc.
Real Madrid without Mbappe can still become a champion in this season, so it's no doubt majority of people will believe in Real Madrid.
Your prediction was not going stright with the odds.
To be honest, it seemed absurd to see why Arsenal is still regarded as the one top candidate to win the UCL while it was always doing bottle job at the domestic league, beside of Manchester City and Real Madrid. Better still for Arsenal, attempt to win the EPL before the UCL caused by it's likely arsenal will become a clown club again next season.
Madrid and City should easily make it to the quarterfinals considering these clubs are still at their peak performances. Still, Manchester City is the most difficult opponent for Real Madrid this season considering i have not seen worthy opponent for madrid other than city next season. Having mbappe indicates how serious Real Madrid is about being ready to win its 16th championship the upcoming season as per what perez hinted on his last interview.
We have more places available for the next seasons. Anticipate a harder competition than in the previous season considering more participants and it's gonna be even more competitive than last season.