There are several elements that makes something newsworthy. Timeliness, Proximity, Impact, Prominence, Human Interest and Novelty. If a story falls under one of these topics, then it is news.
I definitely believe that pop culture is newsworthy. People are obsessed with people, what they do, what they wear, who they’re dating, etc. Pop culture falls under the human interest and prominence elements of news. I know that I am interested in what my favorite celebrities are doing, and read articles about them if I see one. That is why when you’re checking out at the grocery store, there are magazines near you that are all about celebrities, whether it be true or false, because they know that no matter what people will read them. People are interested in other people, especially people who have a lot of impact like celebrities.