Long story short of Google's rise and "fall" in quality: Altavista was dominant internet search engine in the 1990s but search quality was bad compared to what

Long story short of Google's rise and "fall" in quality: Altavista was dominant internet search engine in the 1990s but search quality was bad compared to what could've be done. Google figured out machine learning was the key to success e.g. PageRank. Google got incorporated in 1998. Good leadership(Larry, Sergey and Schmidt) and vivid vision propelled Google to 90% of market share in search. World Wide Web was drastically smaller two decades and one decade ago and Google was still able to "handle" it with already established machine learning algorithms. Fast forward to today World Wide Web is zettabytes big and not even Google can rank it "reasonably" and efficiently. Google doesn't care that much about search quality anymore because they have 90% market share in search, billions flowing in ad revenue plus 99 other projects they need to manage and develop.