Bayern Munich have won 2 of the 6 matches they will play in the group stage. That was enough to make them lead the Group A standings even though they conceded 4 goals in 2 matches. In fact it doesn't matter how many goals you concede as long as you win the match, it is enough to qualify for the next stage.
I think Bayern Munich's performance this season has improved compared to last season, but I don't expect them to be perfect. There are still 4 other matches that they have not played in the group stage and of course we are all still waiting to see how they finish. So I have no doubts about their abilities in each match because basically Bayern Munich is a higher quality team than the other 3 teams in Group A.
Pretty sure Bayern Munich will qualify maybe also be the group winners in this preliminary round, it can be said with the remaining 4 matches they can win even though we are looking forward to how it continues.
Usually Tuchel's team will qualify without tough competition, feeling that this team can go far to the next phase, maybe it will also be a little different when the handle is Tuchel who has experience where he has brought the UCL champion when with Chelsea, or maybe Bayern will feel it?
It's definitely still hard to guess, I feel that Bayern will still be a strong team in the UCL.