This film is intended to be about the way modern German society deals with important issues facing them, and they way they can quickly come under the spell of a "strong leader" ETC. Unintended by the film makers I suspect, was the way the modern left exposed themselves in the way they see those who dare to disagree with their positive views on globalisation and internationalism.
The main message of the film seems to be that those Germans (or Europeans in any European nation) who believe that Germany isn't some giant refugee centre for the rest of the planet, and that Germans have a right to their own indigenous land, not the rest of humanity, are just like Der Fuhrer.
An example of this can be seen in real time news footage of a Swede making the suggestion that asylum seekers, heaven forbid, should actually accept the cultural and societal norms of Sweden. Oh how "Evil" of that "intolerant" man! The film is well made and funny (who'd a thought Germans had a sense of humour?) in places. But take the leftist political message with a grain of salt. Europeans have EVERY RIGHT to be concerned about their demographic integrity and migration from the developing world that never seems to cease. They have the right to be concerned about these things without being demonised as Nazis or anything else.