I think a large portion of the tech industry understands Google AMP is an undeniable threat to the open web. The question is: Is there anything that can be done to stop it?
Definitely one of the threats to the open web would be the web platform falling behind "native" platforms such as mobile platforms. 10 years ago it seemed that native apps are dead, the web is going to win. And then the rise of smartphones has brought us back to a world where we are forever installing native applications. From what i can see, attempts to make the web faster (SPDY, AMP), safer (Certificate Transparency), more open (AV1) are all initiatives i can get behind. The question is : What are other companies doing to ensure the web retains its place as the premier open content / application development platform.
And isn't there more of an incentive towards structuring the web coming from these big players as well? Google and Microsoft (and Yandex) created Schema.org, and are all giving them a priority in this switch from search results to instant answers.
I guess my point is to say that the companies that are locking the web are somewhat playing on both fields and giving webmasters products that are truly improving the web as well. It's far from being a one-sided battle.
AMP seems to be an attempt to keep the web relevant. In countries like India (where i live), most new users access the web via the mobile, and the experience can be far worse than in the west, and absent of initiatives such as AMP you will see a fall off in web usage in general. I am not sure how that helps the open web.
If most people don't care about their data and the security of the web, you can't make them.