Standing separate from the article's revelations, hiring companies to "improve your ranking" is not on its own the same as "spamming Google." This isn't an attack on your statement, but an attempt at clarifying something that could be misunderstood by readers.

There are plenty of ethical, reputable freelancers and companies who advice businesses on SEO related issues like getting title tags right, producing compelling content, good file name structure, and beneficial white-hat stuff like that.