What happened after 7 news sites got rid of reader comments » Nieman Journalism Lab

As Kara Swisher and Walt Mossberg wrote on Recode’s decision to end comments: “We believe that social media is the new arena for commenting, replacing the old onsite approach that dates back many years.”
The benefits to social are that people are already on those networks, already holding conversations and sharing stories, Swisher told me. “It’s not clear why comments are a particularly good part of the [website] experience,” she said.

Not clear indeed ! Here, it’s pretty clear.