I don't think Bayern Munich is getting stronger but it is their competitors like Borussia Dortmund who are not improving themselves to be able to compete with Bayern Munich. If you look from season to season, actually the squad that Bayern Munich has does not have many significant changes, but they are able to maintain their game. But I don't see that in other Bundesliga teams.
Agree, even though last season Dortmund actually had a chance to win the title, but what can we do, Haaland as a key player often gets injured. Moreover, in the new season Haaland will not play for Dortmund and this makes the Dortmund squad not always get a more solid chemistry, if Dortmund can keep Haaland for at least one more season then it is very likely that Dortmund will win the Bundesliga title. But what happened to Dortmund they kept repeating the same way, the case did not make them stronger because they always had a new main squad with new players.
This season Haaland has played really well, but indeed he hasn't been very good this season in terms of fitness. He's been very injury prone this season which makes it difficult for their form this season.
Their performance was erratic as Haaland's condition did not improve.
Now there is new ammunition to replace Halaand who incidentally Haller is also actually quite good in the Eredivisie but indeed it is still quite difficult for them to compete if there is no motivation there.