This defeat does not create a big problem for Bayern Munich and I think this defeat will reflect positively on the team.
I dont know if that lose will be reflecting positively on the team , specially when there next game is against Leipzig on the coming friday.
If Bayern Munich dont win that game then it will be for sure getting very interesting in the first 6 places on the table , the season is still young.
To be honest i would love to see that Munich will be losing it as this gives more fire into the other teams and the race for the title.
However, a defeat is still a defeat and it will be a problem later. Maybe now it is not a problem because they are still at the top of the standings with a 4 point gap, but they should still have a 7 point gap if they had won that match. The season is still young as you said, so it is possible that they will also experience another defeat. However, this defeat will make the opponent see a little bit how to beat them learn from the team that can give Bayern Munich a defeat. That strategy will then be used and it is not impossible that it is very effective for the opponent to implement.