The answer to your query is a no and a yes. It is not that people have become self-centered to intervene while such crimes are taking place. But yes, they are afraid ---afraid of the law, afraid of the system that is in place to handle such cases.
The system in my country would have the police questioning the person or persons who would had got involved in stopping the crime. They may be needed to appear at the court hearings every time the date was set for the hearing to take place, and it may take several years for the verdict. Till then, all witnesses would be required to attend. The story does not end there. The police itself would be asking those who intervened questions like, "Why did you not call the police? Why did you people decide to be a hero? Did you people want your faces appear on the TV news channels as heroes? If you people are going to take the law in your hands, what would we police be doing then?" The questions are endless and hard and dirty and many a time people who came to the rescue would end up cursing their luck later on for having got involved in the matter. As such, people just shut their eyes, kill their conscience when they see something like this taking place, and move on.
That is how things work in my part of the world.