Bayern Munich is a team that consistently retains talented players who are already comfortable with them. Therefore, Bayern Munich is always favored by many fans because the team isn't solely focused on financial gain but is also serious about fighting for the Bundesliga title. The other two teams you mentioned clearly prioritize financial gain through player sales, so they aren't favorites to win the title. But I want them to surprise with a fierce battle next season to make the Bundesliga competition even more exciting and challenging.
Bayern Munich is a club that's financially buoyant, and their goal is to challenge in any competition they will play and win trophies, so for them to achieve this, they need to retain their talented players. Bayern Munich will continue to win the Bundesliga title because other clubs in the Bundesliga don't have the squad depth to rival Bayern Munich in the Bundesliga league, and even when they have a good squad to rival Bayern Munich, they will still sell their best players to other clubs since they prioritise selling their best players for money.