Except, as others have said, that is not what this article is saying at all. That said, your comment seems to imply that you just read the headline, and (perhaps understandably) didn't actually read the article.
I've learned, especially on HN, that article titles can be extremely misleading.
"Mongo tries to make certain things easier, and sometimes it succeeds, but in my experience these abstractions mostly leak. There is no panacea for your scaling problem. You still have to think about how to store your data so that you can get it out of the database. You still have to think about how to denormalize and how to index."
I read the article. That statement makes it sound very much like they thought Mongo would be silver bullet for that feature.