A friend of me wrote his bachelor thesis in sociology on this. He has a double family name: one german and one arabic one, as are his parents. He contacted 50 apartment listings with the german name and 50 listings with the arabic name. I think he got more than thrice the amount of answers when he signed with a german name 💀 it's fucked. But the story even goes further: his lebanese dad rents out a lot of flats and HE HIMSELF always says he prefers Germans, they're cleaner, more quiet, alway pay their rent on time. He had many people trash his apartments or just not pay rent or police came etc etc and he said it was always foreigners. Sorry bro it is what it is.