The article doesn't present complete facts. Regarding zero-sum game, this perhaps was true in the old pagerank algorithm. But I'd believe Google's ranking algorithm has advanced beyond simple keyword density, passing links. What I've noticed is it now gives much more emphasis to user experience. (With metrics like bounce rate meaning the searcher didnt find what he looked for and went back to search results)
We all like to shit on Google but there's no search engine even remotely close to the quality of results. Of course, there's a lot of spam associated with SEO, hacking attempts, spam comments, e.t.c. There are side effects of its algorithm of course, that are negative to web.
Google search result links don’t link to the site directly but go through a Google-provided redirect that presumably has a reference to the original search query.
If you were to go back to the same search result page and click on another result within a short timeframe they will assume you “bounced”.
They also have Google Analytics littering the majority of the web, so I’m assuming that gives them a signal as well.
Google links directly to search results now, they stopped using the tracking redirect years ago. They probably track clicks and scrolling directly on the SERP with JS.
Google Analytics is absolutely not used for ranking purposes. GA is far too unreliable and gameable to be used for anything like that. It's more likely that Chrome and Google Safe Browsing are used for tracking user hits.
We all like to shit on Google but there's no search engine even remotely close to the quality of results. Of course, there's a lot of spam associated with SEO, hacking attempts, spam comments, e.t.c. There are side effects of its algorithm of course, that are negative to web.