This generation is rightfully feeling like they're getting a sore deal.
So it could be:
- the native young population who are now flocking in the AfD
- the people fighting the AfD in the street
- the second generation immigrants born there
- the very recent immigrants
- a mix of all
Because the alchemy of creating a working army and "esprit de corps" is much harder than in a corporation. You cannot just take a modern managerial approach to creating an army.
A mix of all will end up obviously in a disaster but selecting on any group will end up in a civil war or coup.
I don't think that the social situation is as bad as you describe. I just think that people generally don't feel keen to put their life on the line for Germany.
Yes this what I am sincerely wondering: which group (however you want to define it) of relatively young people, do they believe they can leverage "to put their life on the line for Germany"?
When what people get (using their labor to subsidize politicians & boomers via taxes & rent) is the same thing they can get in effectively any country or even under the invader's rule, the incentives to fight said invader become quite scarce.
This isn't even specific to Germany; a lot of people are fleeing conscription on both sides of the current conflict for the same reason - they just don't get enough benefit to make it worth putting their life on the line.