Thomas Muller has done so much for German football and now it is time to give younger players chance. He has had amazing career winning many awards including the Golden Boot. He is legend in German football.
He has contributed greatly to Germany so far and won many awards so his decision to retire from the German national team can be understood considering that he is 34 years old and he wants more rest. There are still many young players who will replace him whose stamina is stronger and he might just Finishing his contract at Bayern Munich which will end next season, there are no rumors of clubs from other leagues wanting to recruit him, so I think after his contract expires, he won't move to any league. His loyalty is only to Bayern Munich and the German national team.
In the future, I am sure that Jamal Musiala will indeed become a leader in the German national team. Seeing that all of his seniors now seem to have entrusted Musiala to lead the German national team. So Muller, Kross, Rudiger and Nueur will give the younger generation of Germany the opportunity to shoulder the burden of the future of the national team. I still remember the young Muller who was underestimated by Maradona, because that was the turning point in Muller motivation to become an ambitious player who always embarrassed those who underestimated him.
It is time for Muller to look for a club outside Germany or more precisely outside Europe to prioritize a meaningful retirement. However, my speculation is that Muller will most likely be part of the German national team staff.