Most people are just overly worried and overly speculative while they forget in this Bundesliga the competition is very tight and they also forget if Munich will always be the team that has the greatest threat to be title holders again in the Bundesliga. I'm not saying there's no chance for another team but the fact is the match hasn't started yet and we can only speculate but we should believe that Munich, Leverkusen, Dortmund and some other big teams have the quality of performance that they deserve to fight for the title next season.
Honestly, if most still believe that Leverkusen will get the same results as last season, I would say no, because from the schedule and experience it is clear that Xabi will not be easy to rotate players to stay stable in the UCL and the bundesliga while Leverkusen hasn't had this kind of immersion to pursue the bundesliga title and want to fight harder at UCL.
Perhaps there is a rational grain in this, Bayer went through this season quite simply without much competition in the Bundesliga, everything may change when they feel pressure every round from the fact that their pursuers will be very close, or even more so if Bayer has to be in the role of a catching up team, which will always be a few points behind Bayern, or even possibly other teams. On the other hand, Bayer managed to keep all the players in the team, they were even able to strengthen some positions, so they have a chance to remain a competitive team, but it all depends on Bayern how they start this season.