I think it crosses the line and I'm surprised Google hasn't issue them a warning, or maybe they have and we just haven't heard about it.
Organic search is still where 80% of the clicks are in search. (only 20% go to paid - though this is changing)
These are easy wins and are considered "white hat" and legitimate tactics:
* Title tag optimization with SEO A/B testing - increase CTR from Google by 10-40%
* Using NLP Content Optimization to increase content relevancy
* Optimize internal linking structure of your site so Google can easily understand your site hierarchy and spread value to important pages
* Build natural backlinks by creating interesting content that people want to engage with and link to (like this post!)
https://www.rankscience.com/coderwall-seo-split-test