Ask HN: Why doesn't Google News have comments the way Hacker News does?

Most news article's comment sections are barren. When the occasional comment does appear at the end of a story, my desire to reply is generally not strong enough to register for yet another account.

But Google already has a huge user base perpetually signed in. And with Google News grouping similar stories together, it seems that would be the best place to host comments about a story in general.

So why doesn't Google News host comments?