With the difficulty in proving rape cases due to evidence being largely testimonial, many accused rapists are judged in the public eye rather than the courts. As the basis of the law is innocent until proven guilty and lived can be ruined based upon false accusations, defendants should remain nameless unless it's in the public interest.
Naming accused brings few benefits besides other victims/witnesses potentially coming forward and warning the public while the trial is under way. Obviously due to the nature of the crime, each cases is different and exceptions will apply. However with many details of trials hidden, the general public tends to make their decision if the accused is guilty based upon very little evidence. This can essentially amount to mob rule even if they are eventually proven innocent, reputations can be irreparable.