On the flip side were these people move from leaves voids and some area's of the EU have become over-crowded and other parts are becoming ghost towns.
Still not everybody can look out the same port window, yet the EU free movement allows it and takes not into account the impacts and disparity of the members countries in the free movement aspect.
WIth that the German solution is not a solution, it will just create a privileged group who have a rent controlled place over those who can not get one at all.
10 years down the line for Berlin, it will be worse as they will shuift the price discrimination into one of space and with that, 10 people to a room hotspots and illegal housing will only grow.
When you have a supply and demand problem, the outcome is simple, but if you handicap that you just create a backlog of problem that piles up and in this case shifts from cost to supply or lack of and does nothing to address that from any angle.
Yes, this is going to be a problem, but will be seen as good by the people in the short term with shortsighted vision.