AMP, while useful for many applications, is simply not relevant for the majority of sites.
I think the issue with AMP is that most people do not understand what it is for. When integrated correctly, it should be a powerful feature for any site. Note that the benefits of AMP are only felt on the first page load, after that point once the user clicks on to another page, much of the speed improvements are gone.
The goal for Google as I see it, was to create platform that would allow users to seamlessly move back and forth between web content and search results. Click on a news article read it, go back to Google go to the next article and so on. It is almost a sort of preview feature, because the user never actually gets any data from the website's server, the first click is drawn from Google's cache. If you build compelling, interactive content then you can draw the user in but otherwise it is unlikely that the user go past that first page.
Google seems to have put a lot of effort to ensure that AMP can be integrated with PWA, and in my view this goes to compelling interactive content. This will allow apps to serve content in the search results. Users can then find app content and the begin interacting with it from the search results. This draws users out of the app only ecosystem of mobile. The more app content they can find the more compelled they will be to use search, for apps and web (sell more ads to app users). And this is of course beneficial for app designers as it will be easier for their apps to be found. If a users stays in the FB walled garden, only FB content will be found.
As for advertising with AMP, you can show AdSense ads just like on any other page. But there is one caveat, (discussed in the Adsense video posted by FrankLeeCeo earlier this week), that is that given the speed with which the content is loaded, it happens that the users scrolls past or bounces before any ads are loaded. If in the past you had a mobile page that loaded slowly, and showed the ads ahead of the content, the user probably saw the ad waited to see the content and then bounced, with a round trip in the tens of seconds. Using the same content on amp, the user immediately sees the content and jumps back in a second or two. No ad view, no interaction, nothing, but the user leaves satisfied that they didn't waste more time and band width. So once again, the content has to be great, or you will be left with nothing.
