A team as big as Bayern Munich needs quality and experienced players for instant results because there is no time for posing anymore, this team needs the title and continues to compete for it.
Rumors about Thomas Tuchel remaining are now getting more intense after Bayern management failed to find a replacement and I think that's a bad decision because Thomas Tuchel has been proven to have failed in managing Bayern so he is no longer worthy to be Bayern's coach.
If they can’t find a better person than him, they should just keep him. He must by now learned from his mistakes this seaosn in order to improve against the coming season. It will be very bad if Bayern Munich signs another coach that is not better than Thomas Tuchel, they will just make their current state worse for themselves. And to even think of it, Bayern Munich was not that poor this season after reaching the champions league semifinals and also finishing as runner up on the table. What have caused them to fail this season will enhance them to do better the coming season. So I see no issues with keeping him for another season. Experience is the best teacher and he has learnt from it already.