...is that journalists generally don't know what they are talking about when it comes to science. They live in a world of politics and history, and they often even screw those up. It is generally accepted that, as a journalist, you don't really need to know the details of something, since an expert can explain it to you.
That said, science journalism, as bad as it is now, is still a lot better than in the 1970s. Then, they really didn't know anything. That's why you get stupid articles in Time and Newsweek about "global cooling" and the "coming ice age", even though actual scientists like Carl Sagan are rolling their eyes at the stupidity of journalists.