What country do you live in? Because there has NEVER been a law 'forbidding opinion as news" in America.
There was a tradition that journalists followed avoiding opinion, but that's it. Fox came along and discovered that if they broke that tradition, people would flock to hear their biased news.
The US does have laws (first amendment to the constitution) that prevent censorship, particularly censuring political opinions. Your proposed law (that never previously existed) would most like fall on the wrong side of the first amendment.