Yes it's true that Leverkusen has sold some of their players but they are also recruiting before the season starts I believe that they have players that they have pencilled down to buy even though that Leverkusen may not be necessarily as tough as before I will still go for them to challenge Leverkusen for the title race
Not only that, but for next season Leverkusen will also be coached by a different coach than last season, so there will definitely be a difference with their previous performance, but I am not sure that Leverkusen will immediately be strong with the change of coach and changes to some players for next season. Because Munich will still be a fairly serious title challenger for all teams in the Bundesliga because Munich is still coached by the same coach and also still retains more of its old players for next season.
In as much as they are selling they are also buying, like Leverkusen is a team I'm still seeing as a big threat to the Germain league next season, because the team is still hungry for trophies and the Bayern Munich that is supposed to give them hard time has just lost one of their top player to injury and that is really going to weigh them in his position, unless they move smart to get a plan B that could cover up till he's back to his fit again or else Leverkusen are really going to give them a tough season ahead, so selling or not I don't still see them to be that easy side this coming season and every other team in that league should watch out for them because those guys are something else.
The coach that led Bayer Leverkusen to win the Bundesliga title and made Bayer Leverkusen a threat to Bayern Munich lately is no longer the coach of Bayer Leverkusen, and we aren't sure if Erik ten Hag could lead Bayer Leverkusen to challenge for the Bundesliga title and be a threat to Bayern Munich next season, so we have to wait until the new Bundesliga season starts for us to know if Bayer Leverkusen will actually be a threat to Bayern Munich or not. The Bayern Munich player who was injured in the Club World Cup by the PSG goalkeeper is a big blow for Bayern Munich because he's one of Bayern Munich's finest players, but Bayern Munich is lucky the transfer window is open for them to replace him, so I think Bayern Leverkusen will not capitalize on Jamal Musiala's absence to beat Bayern Munich to the Bundesliga title next season.