I don't know him, so all i can is guess. All I know is what the News in Germany reported. According to them he just acquired the Data he published. The reasoning behind it is unknown to me, if there was any. In the Media Coverage he doesn't really appeared that smart. Maybe he did it just to brag about it, or he was hoping to extort the people and wanted to prove that he has the material, or it was political because the most victims of him were from the left.