Full disclaimer: Some of my friends are also immigrants from the 80’s. And they’re equally exacerbated by the state of Germany because the country and culture they love is deteriorating out of suicidal empathy.
then i visited asia, and i was shocked how much more friendly and welcoming people are there. if you haven't been there it is unimaginable. same goes for africa. seriously. on a global scale, europeans are the worst in being welcoming. so, yes. germans are not welcoming enough. they are principled however, and it is those principles that made them invite those refugees.
the state of germany is not deteriorating because of empathy, but because of the unwillingness of some people to adapt and adjust to the new reality. this lack of adaption leads to confrontation, and that confrontation is the cause of any deterioration. the culture is not destroyed by immigrants. it is destroyed by lack of tolerance and unreasonable expectations.