Liverpool has a new coach and his performance still does not guarantee success and about Arsenal, that they do not seem to prioritize the Champions League too much because the competition is basically more difficult. Thus, the dominance of Real Madrid and Manchester City will still be the best dominance but still, even if for example the top Premier League teams have the chance to provide difficult resistance to the La Liga teams. But in the end, Real Madrid will always make it to the final.
I wish Arsenal and Liverpool good luck but I also reason with you for saying that they were not prepared for the Champions league especially Arsenal. It's quite surprising to also see Arsenal losing the Premier league to the Manchester City too. Next tournament, Arsenal, Liverpool and Manchester City must up their games to be more competitive in their competition. They need to stand on their feet to defeat Real Madrid at the top. While they are also working hard on taking their premier league, they must also work hard to challenge the status quo at the Champions league. Clubs like Arsenal with Arteta already have the experience including Manchester City with Pep Guardiola. What I expect them to do now is to leverage their mistakes and build on their lapses. There's less competition in the Champions league last year and possibly this year since Barcelona is also not in their best shape. They can use that opportunity to take the trophy home.