To be completely honest Germany, like Belgium, Argentina and Portugal have made a fatal mistake - failure to getting rid of the old legends.
I adore Zidane for bowing out of NT on top, Lahm did the same. Ronaldo Lima and Ronaldinho left European football for Brazil when they knew it was over, Xavi and Iniesta stayed one or two years to long but then left for Asia.
Neuer, Müller need to be gone. Hazard and some older Belgian players should never have been part of this. Messi and Ronaldo need to get the boot as soon as possible. It's about getting rid before the legend becomes liabilities on and outside the pitch.
The culture amongst the young ones can't develop with the old heads being around while being shadows of themselves. But the problem is that the upcoming generation mostly has failed to be good enough to force out the oldies.
In my view Germany should start with picking a new keeper that is 21-25 years old. Ter Stegen will be 32 next euros and 34 in the World Cup, much better to get rid of him too and focus on building a new Neuer. Bayern should think about getting Nubel back from loan asap.