That happens with pretty much every population that gets too big, no? There was a certain name for it I forgot...
"Demographic change"? Germany has the lowest birth rate worldwide while Japan has the biggest problem with an aging society (low birthrates coupled with high life expectancy).
I think we need to take into account the cost of letting them in vs the benefit. Even if they had a much lower crime rate they still shouldn't be let in because they are not contributing anything to the country
Bringing in the refugees had less to do with benefitting Germany and more with a political situation that was pretty fucked up from the start. The whole "Refugees are skilled employees" bullshit arose from the attempt to somehow sell this shit to the German population, I assume.
As I said in the other thread, the refugees were beelining for Germany, so either it was accpeting them in or close the borders and piss off every nation along the balkan route which would also have lead to a humanitary issue when truckloads of refugees are stranded in poor south eastern nations such as Macedonia during winter. That and said people would have slowly trickled into Germany anyway, most likely - Germany simply lacks the necessary police forces to actually close down the borders.
Then again, some corporations certainly don't mind an influx of cheap workforce.
Mind you, I do not like this situation one fucking bit, but just going "Germany was dumb letting these people in" is ignoring the political situation surrounding that decision. It would have been far easier to keep these people close to Syria for obvious reasons, but with the EU farting around until it was way too late, there was hardly anything that could be done anymore.