With the rise of mp3 there was no such thing like „banning“ rap music in Germany. There were albums that got somewhat like shadowbanned, means you were not allowed to advertise them nor sell it publicy to ppl under 18 years. Some artists were sued by the law back in the days but that just rose them to more fame. There are indeed laws and authorities in Germany which take a look at probably racist or anti semitic arts because of our history. Some rockbands got sued for racist/anti semitic/nazi music but rap was mostly shadowbanned and a few years later unbanned from a list we call „Index“ here.

Source: my 15 yo fat ass listening to banned rap music back in the days ;)