As long as Real Madrid doesn't have any problems like Barcelona is currently experiencing, they will continue to dominate every competition, including the Champions League. Real Madrid is the club with the most ambition to win every trophy, they will continue to improve the quality of their squad to dominate other clubs. Real Madrid success in winning the Champions League and La Liga trophies will probably continue next season; they are still strengthened by the players who won trophies this season. Mbappe arrival will also have a big influence on Real Madrid performance in the following season.
Several other clubs are experiencing internal problems which are causing their performance to decline slightly, Barcelona is experiencing financial problems, while Bayern Munich is adapting to a new coach who has minimal experience in European competitions. Only Manchester City is the toughest competitor for Real Madrid in the title race, Leverkusen may make a surprise next season with its increasing strength after bringing in new players in the transfer market.
I agree with you that currently it is only Manchester City that can be a challenge for Real Madrid because in the Champions League competition, but for the next season, I believe the Champions League will be a hot competition. Arsenal will also bounce back, although there are many teams that will not be able to compete next season, and seriously, Real Madrid will have a strong season next season because of the signing of Mbappe. For Bayern Munich, I don't know of the Bundesliga competition, but as for the Champions League, they will experience a hard time next season because their new coach is coming with a new method of play. that they need to get used to before their performance gets better.
It makes sense if we base this on their performances last season. Last season I thought that only Manchester City could provide an interesting match against Real Madrid, and in fact before the 2 legs of the match took place, Manchester City was the more favored club than Real Madrid. We can see that also from the way they play and pressure Real Madrid, especially during the second leg match which took place at Manchester City headquarters.
In recent years they have always met in the Champions League, and what is interesting is how they can become champions after they beat each other. The previous season it was Manchester City who beat Real Madrid and they managed to emerge as champions. Last season Real Madrid managed to beat Manchester City and they also came out as champions, and even when Real Madrid won their 14th title they also beat Manchester City previously with an extraordinary comeback until finally they beat Liverpool in the final with a narrow score of 1- 0.