Spineless moron doing spinelessly moronic things like always because pandering to far-right populist narratives is totally not stupid.
For reference (because the media is refusing to ever tell us the actual facts that don't fit the right-wing narratives):
More than 15 years ago there were ~50.000 people (compared to a population of 81 million) that were due to leaving the country again but hadn't done so already.
15 years later -and with between 100.000 and up to 1 million refugees coming in each year- that number has risen to ... *insert drum-rolls here... ~54.000 people (now compared to a population of 84,5 million).
It's basically a constant. Because there isn't some magical huge amount of people illegally in Germany. They actually get deported or are leaving otherwise. That (rediculous low) number (in a country of that size) is basically made up by people delayed while leaving (often by weeks or some months... which is basically within the delays the stupid bureaucracy is already introducing).