I'd argue it could end up backfiring for multiple reasons. The most obvious one is that it will undoubtedly end up strengthening filter bubbles.

The problems that face us will not be solved by siloing ourselves away from views we disagree with. It might take more effort to filter out bullshit in our current age, but if we're not even aware of the bullshit someone else is feeding off, how are we going to combat it? We need to bring more people into public debate, not isolate them.

Counterpoint: if it provides a false sense of security, then it might have made things worse.

Also, confidence in the press is at an all time low, so there is already awareness. [1]

1. http://www.gallup.com/poll/192665/americans-confidence-newsp...

People read what they want to read. For instance https://en.wikipedia.org/wiki/Motivated_reasoning You can get rid of the fake news outlets, but you can't get rid of fake news as long as there is free speech.

Isn't that exactly what the fake news sites works say?