As a native German, I can assure you that no native German people are being "displaced". This is just a semi-ancient right-wing trope about "Them foreigners stealing our jobs", with the occasional "and women" attached to it.
In the 90's these same people were railing against eastern Europeans, and how their culture and values are supposedly not "compatible with Western Values". Now, over a decade after the EU eastward expansion, rarely anybody seems to remember that part of history and the formerly marginalized are now so "assimilated" that they are part of the very same mobs which used to marginalize them.
Nothing about this whole topic is new, even the surrounding social unrests ain't new and are comparably civil compared to what went on not too long ago [0]. The only thing that's changed is the color of the people that are being scapegoated as the source of all problems and controversy.
[0] https://en.wikipedia.org/wiki/Rostock-Lichtenhagen_riots