Just going to drop my 2 cents about using samples...
I don't see anything wrong with taking a portion of music someone else made and making it your own or using it as a basis. Sure, maybe some people, myself included, would rather make my own music 100%, but there's definitely some creative use of samples and remixing other songs out there.
This one in particular, not really a fan of, but I'm not going to shit on this guy for using samples. Although, I've never heard German rap before, so I thought that was interesting.