Bayern Munich did not win the Bundesliga because of Tuchel. Bayern Munich would not have won the title if Dortmund had won their last match. Moreover, Munich's performance has further deteriorated since Tuchel took charge of the team. Munich does not play well in Bundesliga matches either. However, the Munich management will definitely give Tuchel enough time and money to work. If Munich do not transform into a strong team by the middle of next season, then the Munich management may once again look for a new coach by sacking Tuchel.
Even while Bayern Munich declining play and failure to win the Bundesliga under Tuchel raise questions it would be premature to pin their problems entirely on him. Numerous factors especially the performance of opposing teams like Dortmund, affect the results of football games. Since frequent coaching changes might not produce the intended outcomes Munich administration has showed faith in Tuchel by giving him time and resources. Munich should be judged on their overall record not just their performance in the Bundesliga. Recognising that developing a successful squad takes time and requiring patience when switching to a new coach and playing style. The administration of Munich will probably evaluate Tuchel development holistically taking into account both on field outcomes and the underlying development within the club.
Actually I was not interested in entering Thomas Tuchel's name at a time when they were up and down and in the end they went on to win the Bundesliga title with luck. Because I didn't expect much from the start with a new coach who had a very short time to study his entire squad well. I actually question more why management has to make decisions when they have to have very good chemistry between coaches and players. The change in strategy from the old coach to the new coach will create gaps because they have to adjust again, that's what got them in trouble with Tuchel.