Facebook: fake / not fake

Interested to see how accurate this data will be. After all, wasn't it because people couldn't detect fake news that this problem became so widespread in the first place? Wonder if we'll see this get misused as an ersataz 'I don't like the source of this information' button as well?

From the examples that mashable shows, it seems more like a measure against clickbait than against fakenews (which ofc uses clickbait)

I'd like to learn about their reasoning as to why this could be considered an effective corrective action.

Clever, putting your users to work, to improve your product.