When power is too concentrated in one area, its never a good sign for the common good.
The speed improvements and mobile friendliness should be the only criteria that the Google ranking engine should use for boosting the SERP rankings of these articles using it, not simply the fact they use AMP. But objectively measuring the quality of these page vs other unoptimized sites - which I hope is currently what Google is doing. That way there is nothing monopolistic about it.
Considering how awful most news sites are JS/ad-wise Google is attempting to solve a problem the publishers themselves created. Sites like Forbes are notorious for loading mb's of ads and they have that ridiculous quotes splash page. It also does away with annoying pop up modals news sites love to use.
So if these sites rankings are getting hurt because of their failure to offer good caching, image optimization, reducing the size of JS assets, etc, etc, to offer a competitive experience with AMP pages then I see nothing wrong with that. The competition will be good for users.
As long as publishers are voluntarily using this because it improves their UX then I'm fine with it.
Ideally in the long run this is just a stop gag until these publishers learn how to optimize their own sites. Then they can move off the platform. I don't see it as a viable permanent solution given the compromises involved and nor should the publishers.
My only complaint is the URLs are prefixed with Google.com making it harder to share direct links. But otherwise the UX improvements are worth the tradeoffs - in the meantime at least. If it's still the default in 2-3 yrs and news sites haven't fixed their sites I might take issue with it.
Edit: I did some testing and it looks like Google puts AMP articles in a carousel at a higher prioritized position vs other news stories. They aren't mixed with other news sites... that's not cool.
https://medium.com/@pbakaus/why-amp-caches-exist-cd7938da245...