What you've said would make sense if there's broad agreement that there are multiple opposing viewpoints/explanations all of which have some roughly equivalent level of credibility.

So for example, despite me not agreeing with it, and believe it to be completely refutable by looking at the evidence, I will concede that the concept that welfare payments might make at least some people lazy is a position that needs to be accorded roughly the same level of credibility as my own position (it doesn't, and the amounts of money and moral hazard involved make it largely irrelevant). Someone reporting on social policy questions and discussing the pros and cons of a welfare system would be remiss in not mentioning and examining both these perspectives (and others, probably).

In the case of raining/not-raining, this is clearly (to me) absurd. One of the POV's is right and one is wrong. There's no need to say "some people say <wrong thing>". It's just wrong.

The problem IMO is that many issues fall into the gray zone between these sorts of examples. For example, I'd say that people who claim that tax cuts for the wealthy lead to an improved economy really don't have any evidence whatsoever in their favor, and that reporting on their position as if it is somehow a credible economic policy is giving credit to something that is demonstrably false. But there's enough wiggle room there that a journalistic organization might still feel, even after myself or Krugman have shown them the evidence that this view is demonstrably false, that they should cover the position of those who make this claim. They can enuniciate their perspective eloquently and clearly, and they sound as if they have a legitimate position that deserves consideration. Journalists are very reluctant to make this judgement call.

The real problem, I think, is something I alluded to up-thread. It's not really about presenting particular perspectives. It's about critical thinking, both on the part of the audience but also the journalists. It's about challenging the claims made with perspicacious questions, and pushing for answers until they are given, or it becomes clear that someone is unable to justify their beliefs. The problem in the current media landscape is that if someone actually does this, they will rapidly be unable to bring these skills to bear on anyone who actually matters. So they don't. They do what NPR does so often - put the voice in front of the mic, and "let the audience decide". Don't challenge, don't ask difficult questions, don't follow up, don't call out obvious and common logical flaws and fallacies, don't ask for evidence.