In essence, if Xabi Alonso really wants to leave Bayer Leverkusen then of course, I am sure that next season Bayer Leverkusen will not be as good as this season. Unless, for example, Xabi Alonso still stays at Bayer Leverkusen for next season, then this will make the title competition still a difficult competition. But anyway, if Xabi Alonso really leaves then yes, of course Bayern Munich will again to dominate the Bundesliga even if only with Tuchel.
Of course. The reason is that Leverkusen's current success is thanks to being trained by a genius coach like Xabi Alanso. Since Xabi Alonso became the coach of the Leverkusen team, the performance of his players has improved. Of course if he leaves, Leverkusen's performance will decline and as you say, Bayern Munich's dominance will return. I hope Xabi Alonso doesn't leave next season, because I want to see how far Bayer Leverkusen plays in the UCL under Xabi Alonso. I also hope that even if he leaves, I hope he trains Real Madrid because currently Ancelotti has extended his contract with Real Madrid so I hope Xabi stays at Leverkusen.
But unfortunately, Bayern Munich has decided to terminate Tuchel contract at the end of the season and therefore, we will wait to see who the new coach Bayern Munich will next season to replace Tuchel. Because yes, if Bayern Munich appoints a better coach than Tuchel, then it is certain that Bayern Munich still has a chance to dominate the Bundesliga again next season.
It is natural that Bayern Munich terminated Tuchel's contract until the end of the season, because under Tuchel's coaching he did not develop significantly in either the Bundesliga or the UCL League. Even though Bayern Munich's squad can be said to be luxurious, especially under Tuchel's tutelage, they have managed to bring in great players like Kane and Kim.