In a nutshell, the media world as we know it (or used to know it) is in a state of flux unlike anything we’ve seen before—and that includes the invention of television itself. Many mainstream media companies, meanwhile, are still trying to come to grips with the concept of “cord cutting,” which is a little like worrying about a flat tire on your bicycle when you are stuck in the middle of a 12-lane highway.

The media economy used to be all about monetizing a handful of content channels, which were controlled by a handful of major media platforms like TV networks and newspapers. Now, the economy has shifted from being supply-based to being demand-based, and attention is the main currency. Internet users spend that currency in many different ways, and digital-only platforms like Facebook and YouTube (and Twitch and SnapChat) are the ones best equipped to monetize it.

David Pakman, former CEO of eMusic and now a partner with venture capital firm Venrock, did a good job of sketching out the shifting media landscape in a recent piece he published on Medium, in which he took a look at where Internet and mobile users, and particularly millennials, are spending their attention.

The macro shifts that Pakman is talking about have been described before, by people like Kleiner Perkins analyst Mary Meeker in her annual Internet Trends presentation, and in reports like the ones the Pew Center releases from time to time about the state of the media industry. Millennial users are spending a growing amount of their time on mobile devices, and vanishingly small amounts of their attention on traditional media sources like TV and newspapers.

So where is all of that millennial attention going? A huge proportion of it is being devoted to apps, Pakman says, with gaming and a variety of social networks taking up the majority of that time. Facebook dominates this new media landscape, not just because it has a billion users who spend an average of 40 minutes a day on the platform, but because it also owns Instagram and WhatsApp. The top four most popular iOS apps belong to Facebook.

Facebook’s dominance, and the control this gives the platform over traditional media companies is a big part of the attention shift of the past decade. But there is much more going on than just that. Tens of millions of people spend hours watching streaming e-sports through the Twitch service (which Amazon bought for $1 billion last year) or through YouTube, and millions more watch videos by YouTube creators like PewDiePie, a Swedish man who got 4 billion views last year.

Even that just scratches the surface of what has been happening with digital content, thanks to platforms like YouTube, Twitch, SnapChat and Instagram. There are streaming video creators who routinely draw more viewers than the NBA finals or the World Series, Pakman says, but these new forms of entertainment tend to get surprisingly little attention from the mainstream media.

“The audience sizes being drawn to these new platforms are massively dwarfing audience sizes of traditional media properties. You wouldn’t know that from reading the ‘media’ sections of The New York Times and The Wall Street Journal, who still produce thousands of stories discussing the rise and fall of cable TV programs… yet they comfortably ignore YouTube celebrities, Viners and Twitch broadcasters with much larger audiences.”

As Pakman points out, it’s also somewhat surprising that “none of the traditional media companies have invested in, built or acquired any of the hundreds of global properties which have hoovered our attention away from their legacy properties.” Why didn’t a TV network or mainstream media entity acquire Twitch, which pulls in a million simultaneous viewers on an average day? Why wouldn’t someone have bought or invested in Vine or Periscope or SnapChat? For that matter, why didn’t a media company buy Minecraft?

The underlying principle is simple: Where the attention goes, the money will inevitably follow. And right now, the attention of a large chunk of the population is being diverted away from traditional content and information channels, and platforms like Facebook and Google are busy vacuuming it up. Many existing media and content companies face a future in which they are just suppliers to these platforms — or even worse, find themselves cut out of the attention economy altogether.