This is the video on the Airbnb piece: If you want to win in the 21st century digital economy, you must control or influence demand, not supply. In the industrial age economy, power went to gatekeepers of supply. Today, the empire builders are those that control demand. This is possible because digital supply is unbounded and unconstrained, making it largely not a factor. Digital utilities like Google, Facebook, and Airbnb which control demand become the new gatekeepers.
In the digital age, what matters is not who controls supply, but who controls demand. Supply is largely infinite as there are many ways to get to the web, and because it is infinite, users congregate to platforms to help them navigate and make sense of the web.
In 1980, before the digital age as we have it today, the most powerful people in media were newspaper publishers. They were the people you needed to reach to get your message to the world. They decided what everyone read on the dailies and they were powerful. They controlled supply and by controlling supply, they shaped everything including advertising.