Since "the best" doesn't exist, just like there is no magical professional that has unique insight into the mind of the user making the search, a search engine could become pretty great by simply not taking decades to remove scams like the one described in the article from the top of search results
And the notion of "the best" is inherently subjective
There are many criteria for "best" that are acceptable to many people, e.g. lowest price, proven high quality ingredients, efficacy, etc. "Website with high reputation that happens to be running ads for company XYZ" is usually not how people define "best".