Re: Fake news is fake news
That's the biggest part of the problem, sure, but you're overlooking the multiple layers of obfuscation and laziness involved. It's not (just) Facebook that's misrepresenting stuff as "news": it's also Facebook users, and indeed the news sources themselves.
The economics of news reporting is fundamentally broken. (Basically: there is no plausible way to make money out of reporting facts. People think that facts are valuable, but only opinions can be monetised. Therefore there's a strong structural incentive to present one as the other.)
That's not actually Facebook's fault, although they're certainly not doing anything to improve matters.