1. Of the entire audience being catered-to, almost none of them will have the inclination/money/time to become meaningful experts in violent mass-shootings.

2. The kind of information crafted by the mass-media is too low-quality to assist anybody towards that goal anyway.

3. People who are interested or competent in the field will instead acquire their data through entirely different mechanisms anyway.

4. The mass-media coverage is actually counter-productive to the goal of competence. In the search for filler, it is increasingly likely to host terrible "experts" or to portray news-anchors as experts. Among viewers, it creates "armchair experts" after 5 minutes, instilling them with a false sense of competence.

5. Finally, the popular style of mass-media coverage harms society in general, through encouraging additional unstable individuals to act.

Being informed is almost always better.

The point is that media is making mass killers into celebrities and that encourages more sick (read depressed, lonely) people to perform acts like this.