The strongest teams in the Bundesliga were Munich and Dortmund. Dortmund managed to find some talented young players. However, they did not want to dominate the Bundesliga or win the title. Their main target was to make money by selling young talented players. That is why we are not getting a better performance from Dortmund this season.
Yep. There are no other teams who can be as strong as Bayern Munich and Dortmund in the past. But we have Leverkusen now, Leverkusen becomes stronger under Xabi Alonso's management. Well, Dortmund is very well known as a team which is easily selling their top players. Even worse, they often sell the players to Bayern Munich. It is also the reason why Dortmund is difficult to be the champion, they only can be as a runner up. It is difficult to perform well if the mainstay players are leaving. However, it is true that Dortmund prefers earning money over winning the title.
Hopefully, the Bundesliga will become more competitive next season.
Bundesliga has been quite competitive recently. Sure, it will be more competitive in the next season. It is because more teams in Bundesliga become stronger and they seriously build their squad with popular players. I'm sure domestic competition will be more interesting in the next few seasons.