I think it's rather disingenuous to publish an article based purely on speculation. The media should be fact checking stories before they are published. Just providing a disclosure statement on someones hunch is unethical in my view because it's not news; someone's having a stab in the dark and hoping that later on it might be right.
Unfortunately we rely on honesty from the media, thing is it's like a maths problem, if a guess is made and it's correct, the method is still wrong. The person making the guess can make out like as if they knew what they were doing, but in reality they didn't have a clue. We rely on the media upholding standards in their 'method' to news gathering, and the degradation of these standards is why the collective mainstream media has been getting things so wrong. The media has burnt quite a lot of good will with proven conspiracies (Journalists collaborating with the Clinton campaign), bias, yellow journalism and basic dishonesty with their readers, not to mention the humiliation of getting their predictions so wrong. I think the that 'post-truth' and fake news hasn't been engaged by the public as much as the media would have liked as a result of that lost good will.