Exactly, Bayern Munich has a big challenge this season that cannot be underestimated. Leverkusen and Dortmund, at least those two clubs will be their tough competitors.
Especially if we look at the last match Bayern Munich vs Wolfsburg, even though they won, their game was not effective and accurate enough.
Check these statistics:

Google/bundesliga-wolfsburg-vs-bayern-munich
They have 71% ball possession, but only 8 shots on target, and only 2 goals created + 1 OG
I look forward to a time like this where the Bundesliga would not be a sole dominated league as it has been for many years with Bayern Munich going unchallenged. It’s always difficult to even gamble on them even as the odds are always very low, 1.2 odds and below for Bayern Munich win and at times, you find them loosing when least expected.
Bayer Leverkusen did the unexpected last season and such performance is anticipated this season with Dortmund on the side to challenge Bayern even further. RB Leipzig is one team that would have been added to the least of contenders but, even them are not so consistent.