Welcome to Schufa in Germany, the “social credit score” without which is almost impossible to rent or buy in most German cities, if the report (which most folks hardly know how it gets calculated) doesn't have the right numbers on it.
Only my very first rental back in January 2005 wasn't required, however I would say either it wasn't as widespread, or I was very lucky getting the flat from a university student leaving the apartment and her father (the landlord) fancying me.
Most of folks on my friends circle have similar experiences.