I'm not really sure about Kompany abilities because he is not an accomplished coach, Bayern Munich will sink further with him and it will be increasingly difficult to compete in the Bundesliga and Champions League. It looks like Kompany time with Bayern Munich will not last long, he will experience difficulties in the Bundesliga with increasingly competitive competition, while in the UCL he has no experience there at all. My prediction is that Bayern Munich will end the season again without winning any titles.
Even though I know that the team Kompany managed last season was relegated, that doesn’t mean we should underrate him to this extent. Bayern Munich management is not looking for bad things for the team, they know what they are doing, and that is why they don’t really care about what their fans will say because they know that their decision is for good and they know that Kompany will actually do well managing the squad. They know the potential they see in him before hiring him to manage the squad for them, so you are saying they will get worse.
I think you are mid understanding something because Kompany leveled up Burnley to the Premier League. I believe you know that, and again by next season we can’t expect much from Bayern Munich because they have a new coach and things will really change before they comeback strong since the coach will bring new methods that they need to get used to before their performance gets better.