This is the key point and the clickbait-y headline notwithstanding, it's a very valid point. People look at Google and say "wow they have super-smart engineers and let them work on whatever they want with 20% of their time" and tons and tons of products sprung up all over the place.
But after a while, management seemed to back off of that philosophy quite a bit. In 2011, Google killed off many of its less successful projects, including Google Labs, and I read in some nook or cranny of the Internet that the 20% time has been quietly deemphasized over a number of years.
So the idea that you can just hire smart people and magic will happen, though often copied and lionized, is not all it's cracked up to be. <Insert quip about monkeys, typewriters and Shakespeare here.>