I believe the idea is to prevent the perpetrators of such crimes from benefitting from the publicity caused by their crime. There's been a big movement to try to get news organizations to focus more on the victims of crimes.

(I have no personal expertise to judge whether this is an effective approach or not. Just expressing what I suspect may be the reasoning.)

I think that it’s bad to amplify extremist views (see the number of shooters who glorify the Christchurch killer). In this case I don’t think that’s a huge risk, though.

Because it encourages mob justice.

What, we are going to harm some guy in jail?

This is absurd. Society can't function if knowing things about suspects is off limits. What are we children?

There's laws against crime of the sort you imply. We know the guy did something and that he exists. If people can't handle learning details about someone's background without doing something illegal, those people deserve to be behind bars too...not dictating information censorship for the rest of us.