Thomas Tuchel has only coached Bayern Munich this season, so if you want to see if can bring Bayern to play well, have to do it next season when they play in the Champions League.
For the Bundesliga they have played well and ended the season in 1st position having the same points as Dortmund in 2nd place.
Bayern Munich will also compete in the DFL Super Cup final against Leipzig, I'm sure Thomas Tuchel with Bayern will be able to win the cup.
for me it's not too bad Tuchel even though he only trained Bayern Munich last season even though he failed in the champions league but at least he was able to dominate in the bundesliga and there is a little confidence in the following season maybe Tuchel will be more enthusiastic about bringing Bayern Munich to be able to get the best position in the champions league at least until final round.
Bayern Munich's dominance was maintained in the final minutes of the season because actually Bayern Munich almost broke their dominance if Borusiaa Dortmund did not fail to win the last game against Mainz. So there are actually a lot of things that need to be fixed if they still want to continue their dominance in the next season. Bayern Munich is rumored to be bringing in a defender from Napoli. I think that's important because one of their weaknesses is defense, so they have lost several times to teams that are not considered capable of beating them, and it looks like Bayern Munich are serious about improving their team because they also made changes to the CEO and also sporting director, next season will certainly be different.