I've always questioned the long-term viability of AMP. It's geared toward news sites - almost all of which are relying on advertising revenue to pay the bills. Until such a time comes where news outlets figure out a new revenue source, they need to maintain control of their advertising.
Ultimately, AMP is Google's response to a situation that they created (or, rather, a situation that they are in the process of creating). This one could be a more difficult issue to overcome in a decade than the one they created by openly giving links a cash value back in the early 2000's.
A year or two ago, almost all major news sources provided a separate lightweight mobile feed of their content. It was the same as the main page but with just one or two advertisements compared to the everlasting gobstopper worth of ads on the desktop version. Now, Google is saying - don't do that. Make your site responsive, don't serve it from two URLs. So now all the news sites are switching over to responsive sites.
There's a dirty little secret about almost all responsive sites, though... unless you're going to spend dozens of thousands of dollars on your site, the content you see is controlled by the CSS. I scale things for various screen resolutions and I hide and show things for various resolutions - all in the CSS. This is fine and dandy and it looks good, but... even if I make most of my ads be "display:none;" on mobile devices - they still need to load. They just don't show up on the page. Most responsive sites have a mobile menu that is hidden on desktop and a desktop menu that is hidden on mobile. No matter how you load that page, you're still actually loading BOTH menus - it's just that you can only see one of them. Serve a high resolution picture for desktop and a lower version of a picture for mobile and use CSS to decide which one to show.... you now are forcing your visitors to load BOTH images and then show them one. (This is why I just serve up the image resolution that is required to look nice on desktop and just scale it down for mobile. It's a better solution than serving up two images).
The ONLY way you can ACTUALLY speed things up is to actually deliver different content for mobile users and desktop users - something that most news sites (and many large commercial sites) were doing until Google told them not to. Back then you'd detect the device and redirect them to the url/server that was delivering that content. Now, if you want to do it properly, you need some software which detects the device being used and then actually serves the variable content from the same URL. And you still need to maintain two (or more) sites. Plus... what if I'm on a tablet which your server decides to serve up the mobile version, but I really WANT to view the full-color full-featured version. Nope.
The irony of AMP is that it solves this problem by replicating the solution that news sites already had - by serving the watered down version of the site from a different server/url. <facepalm>
Ultimately, AMP is nothing more than a power grab using a Cloward and Piven strategy.
For those who don't know what that is... it was a strategy designed in the mid 1960's. The idea was to overload the federal welfare system to make it go broke so that they could run in afterwards and say, "We'll save you!" and initiate a socialist guaranteed annual income program. Many think, for example, that Obamacare was designed to follow this same strategy. They could never get a full socialized single payer healthcare program approved, so the strategy then became one of creating a program which could pass, but that would actually collapse under its own weight over time. Then, once everyone is dependent on the system, and now it doesn't work, they've created a crisis situation and they can run in and say, "The only solution is to instate an emergency socialized single payer program!" Which, of course, would pass because it's the only thing that would take us out of the crisis.
Google is doing the same thing here. They're leveraging their power hold by saying "Do what we say, or you don't get any customers." But, what they say (serving responsive sites instead of serving different sites for different purposes) creates a new problem. Now we have a crisis because mobile content being served by the web is too bloated and needs to be pared down. A responsive page is often around 150% bigger than a page that is served directly for the device it's being displayed on. And if you are on a mobile device, you're being served about 300% more content than you need to have downloaded if sites had just kept doing it the way they were doing it in the past. So, of course, Google is here to save the day: They call it AMP.
It's a power grab. They didn't have any control or stake in mobile before. Now they do (or at least they are trying to gain one).
AMP is doomed by the simple fact that it goes against everything that the web stands for. In five years, we'll be talking about AMP in the same way we talk about Google Answers and Orkut today, (HINT: We dont.)