You aren't stopping conversations. And, FB already has to do that in countries with laws that control those aspects of the free press.

Would there be any difference at this point?

The licensing of journalists is coming.

> You go to cnn.com [...] "outrage stories with headlines for clicks, stop incentivizing that behaviour"

CNN is one of the example of news organization that lives on outrage. There's not that many news sites left that avoid clickbaity headlines and fueling outrage. Social media helped to advance that, but it's not now - cable news and just their websites discovered that it works before social media.

Should this article and discussion be allowed on HN?

You might be underestimating the percentage of the population for whom the internet is Facebook. Just like AOL a few decades ago, there are still plenty of uneducated people who genuinely don't know how to navigate the internet on their own. Those people then go on to effectively get their news from Facebook or similar.

Because people want to use social media, and they're going to keep doing it. And people talk about news.

They're still going to talk about it with friends and family. Except, instead of at least linking to an article, now they'll have to share it via selected bits and pieces that FB can't censor (or via pure interpretation).