There may be some growing pains and hitches. Part of the process. Building unity and a winning mindset takes time. Instead of pouting over a loss or two, take a big breath and let the man do his thing. A championship squad and Rome weren't constructed overnight
If many others can reason in this direction, they won’t be looking down on Kompany as not being the perfect person for the coaching job at Bayern Munich. It is unknown to us what happened between them before an agreement was signed for that long with him. He is still in is grooming stage as a coach and was still awarded a big contract in a big club, don’t you think they know better than us what is to come for them if he doesn’t succeed as the manager?
It may just be as you’ve said it, he is a long term project with the team. The results may not start coming from the first season as he will be building the team gradually and replacing some players where they are not more fit in the club. Kompany has done it before at Derby County and that gave him the rise to manage a premier league team. Another opportunity is now with him and I don’t think he’ll let this slide by without trying his best to make it a success yet now again.
It just feels strange when Bayern Munich appoints Kompany, because basically Bayern Munich always expects quick success even though it remains for a long-term project. But anyway, if for example Bayern Munich really wants a long-term project with a process that is not fast, then I'm sure Bayern Munich has previously kept Nagelsmann or maybe Tuchel. But anyway, when the two coaches approached failure, the fact is that Bayern Munich also did not hesitate to fire Nagelsmann suddenly.
After that, with Tuchel's failure due to heavy opponents Bayer Leverkusen last season, the fact that Bayern Munich also could not afford to be patient for a long process for Tuchel, because Bayern Munich also made a quick statement with the plan to fire Tuchel at the end of the season. It has happened, but what makes me unbelievable is the appointment of Kompany because basically Kompany also still does not have much great experience like Nagelsmann and Tuchel, but Bayern Munich seems to be gambling with his choice like this.