David Hone has a good piece on what constitutes an appropriate subject for debate, and how the media fails.
The truth however, is near inevitably that there is only a very small minority making a disproportionate noise about their case. There is no debate over evolution, or the dinosaurian origin of birds, or that HIV leads to AIDS, or that climate is changing, or a great many others. That there are real, accredited scientists who do not think this is the case is not in doubt (sadly). But that this represents a real schism in the scientific community, that large numbers of researchers take these positions and that it occupies a significant amount of scientific research, or that there is good evidence for that position is certainly incorrect. One or two people arguing a point (and often doing so primarily in the media) does not make a debate.
This for me seems like the opposite of what good journalism should be. Surely the point is to provide a representation of the true state of affairs rather than spin (even if unintentionally) the fact that there is disagreement as something that is effectively 50:50, when it’s 99.9:00.1 or less. This can be humorous from an insider’s position when one sees the media triumph a paper as ‘reigniting the debate over x’ when in truth the researchers have looked at the paper, noted an obvious flaw or that it simply rehashes old and incorrect arguments or data, and carried on. The flipside of this is where there really is a scientific debate, in which case the debate is not reignited at all, but merely still going on, it has merely come to the attention of the press and public again which is not the same thing at all.
At least I have noticed over the years a decreasing tendency for newspapers to try to couple every discovery about evolution with a quote from some creationist somewhere, so I think the situation is slowly improving.