Excellent point. Newspapers and television news organizations are businesses. They are not run by heroes, by warriors, by crusaders. They are run and operated by people who want to go to work, do their thing, an go home at the end of the day like anyone else. Unfortunately, they chose to be in a business that involves communicating with huge numbers of people, and the information they put out can have unexpected and inconvenient consequences.
For this reason, they tend to do their reporting in a way that minimizes the potential hassle factor to themselves. As you point out in your post, this causes them to tend to pull their punches if they might inflame some population that might, say, bomb their offices or assault one of their reporters. The mainstream white European culture becomes the whipping boy, because soccer moms and cell-phone toting professionals are not going to throw rocks through the windows of the newspaper's headquarters building.
I think you have put your finger on one of the forces driving political correctness and media bias: it's just a way for those in the media to minimize the personal "hassle factor." I mean, come on, it's only a job, right?
Other factors that play into the same outcome:
1. Pseudo-intellectualism
2. Ivory-tower detachment
3. Desire to make business pay to get their good news out
4. Herd mentality
5. Phony "creativity" (common sense says this, but common sense is so boring, so I'll say that)
6. (insert your ideas here).
(steely)