I think the point being made is that these comments are taken, on some level, to be as valid as the expert's scientific opinion- a trend definitely mirrored in cable news.
Yes, everyone has an opinion. Lots of people will have opinions contrary to the experts (read

eople who spend their entire lives doing this stuff) in a given field.
Does that make their opinion valid? Not really.
Does it make it equally valuable, such that they deserve to be sitting across from an actual expert on a TV show?
Fuck no.
Honestly, I never, ever liked the comments section on news articles. For intelligent articles it discourages thinking about the content ourselves in favor of seeing if someone said something that makes sense to you (or to be less charitable, offers you the chance to find a comment that allows you to keep your same views, i.e. confirmation bias). For dumb articles it allows you to argue back, but the flame war traffic just encourages the posting of more shitty articles. It serves no good on any site, I think.
I was so dismayed to see the "comments" sections spread from yahoo news to every other news site ever. I know it brings in page views but by god is it a useless cancer.
(I've seen some obvious "troll bait"
articles even here on the Escapist, which is kind of sad for a news site. Witness that "sexiest female characters" that a lot of people laughed at as trolling, but I think it's pretty unprofessional and news-damaging for a news site to troll. Of course if I'd posted that opinion in that particular article I would have just contributed to its traffic, so that was a lovely catch-22. This is a perfect example of why the comments section is useless garbage.)