If you read the article, it's a system to detect fake reviews in general - there's no mention of bots or spammers at all. By looking at their methodology it's clear that it targets people who write fake reviews, not bots.

Also, it's not as if every spammer in the world is aware of this software and will adjust to it accordingly. In fact, I'd say the vast majority wouldn't even be aware.

Lying well is actually really difficult and doesn't come easy to many people. The differenced between a review written from experience and a review written from someone's imagination may be slight, but I think there will always be markers.