This article is OK so far as it goes - there's certainly no doubt that academics are being scammed by scam journals and conferences. I get their invitations all the time, as does pretty much any other author in the field. At the same time, I think there's a bit of a naivety regarding the reliable sources. For example, it seems odd to uncritically agree that “There’s one legitimate impact-factor supplier, and it’s Thomson Reuters.” And the assertion that you've "burned your research" if you publish it in a shady journal is nonsense. The word stands on its own, no matter where it was published (but one wouldn't expect a publisher to agree with this, I guess).