Realities have evolved; French politicians could use the German guilt until the 80s but since German politicians are not so easy to maneuver and now they respond with the relative economic weight of the 2 countries which is much in favour of GermanyThe whole idea of the brigade is one that I have always found puzzling. The French and Germans are not exactly the best of friends, and the French are quite active operationally, unlike the boxheads.
France and Germany used to be apparent best buddies but in the past couple of years they have been at loggerhead on many important issues, especially in the defense and foreign policy fields.
The German resent French initiatives in those field (TBH they are often badly coordinated with allies and completely out of the blue at the whims of the president), the fact that France tries to internationalize African issues that Germany isn't interested in at and the fact that France doesn't mind BREXIT while Germany fears it.
On the other hand, the French cannot stand anymore the complete immobility of the end of the Merkel reign, the waste of rations that German forces are when deployed in international Ops, the fact that German initiatives such as the open door policy towards migrants has put the EU project in jeopardy and the lack of drive towards the PSDC even though Germany has secured a lot of top positions in Brussels.
For all those reasons, there is now always a collective breath of relief when the German forces announce they do not participate in a French sponsored initiative (such as TF Takuba for example) as a German participation is really seen as much more a problem than a solution.
The silver lining of this cloud is that BREXIT and lack of common FRA/DEU interest has brought FRA and GBR closer in many defense fields.
And in order not to stray from the theme of this thread, here is a NVA Frau in uniform: