Bayern Munich will have no problems to extend the title. With or without Lewndowsky, they won't notice. They may miss him in the Cl if they have to play against PSG. But Bayern can continue there too, it can fall both ways there. I wonder which of the top teams can keep up the level. We know from RB Leipzig that they have a strong team, but Union Berlin could fall quite far back with this selection. If they reach European football, that would already be a great result. frankfurt is on a roll in the Cl, but things are a bit less in the league at the moment.
The main homework of several teams such as Bayern Munich and Paris Saint Grmain is the Champions League, they don't need to be doubted in the domestic league because they have enough strength to defend their current title. But when moving to the Champions League it will be something different, this is inseparable from the competition in the Champions League is very tight. Once they make a mistake they will receive a penalty by being eliminated by the other team.