However, it's more subtle that that. It is a fact that so-and-so holds this-or-that position or belief, even if that position is wrong or incorrect. Those kinds of facts should be reported on, especially when they encode the beliefs and position of a major politician or political faction. A reporter also cannot outright contradict such a person, except in very clear cases, without seeming partisan, so they have to juggle with the prominence or try to inject a more authoritative counterpoint.
It's a hard line to walk, even when newsrooms were fully staffed.
If you ignore them altogether because they are a bit crazy in one regard (well, maybe a lot of regards), then you are throwing out the baby with the bathwater.
"Side A said X"
"Side B said Y"
Well, that's of no help to me. I could simply go to those PR pages myself and see what they said.
So this is not about ignoring them, but about not giving equal credit to both view points or being mouthpieces to propaganda.
In fact if you investigate it, you'll find a lot of so-called "climate change denial" is not so much denial as skepticism about the robustness and motives of climate science. There are some remarkably famous climate change skeptics you wouldn't expect, like a former head of Greenpeace who wrote an interesting essay that basically claimed oceanic acidification (due to extra CO2 being absorbed) was junk science. I didn't bother digging in to the merits of that specific debate, but when even the former heads of ecological charities are flagging problematic scientific practices, and when I've witnessed quite a bit in other non-climate fields, it's not a big stretch to believe that academia may have been exaggerating or mis-interpreting things to unlock grant money. Certainly other areas of science have developed a big problem with that (p-hacking etc).
For instance, your climate change (which was called until a few years ago "global warming") test rubbed me the wrong way because you mentioned the "climate scientists". There is no such thing as a climate scientist because there is no climate science. There is climate research or climate studies but not Science. Science means application of Scientific method: (a) making observations -> (b) formulating hypothesis (falsifiable predictions) -> (c) proving or rejecting the hypothesis through experimentation. Climate studies lack the third step and therefore they are not science.
Should I dismiss the rest of your argument based on my own test of "the person fails to understand the difference between science and ontology"?
We are seriously in times where one side denies climate change. There is zero point in giving them time because it elevates their point to being equal to the one backed by actual climate scientists, not industry that has a vested interest, like coal, in continuing to deny it.