what does google get out of it? The experience is better for users who like fast, lightweight pages, but as far as i can tell there's no tangible direct benefit to google when you load an AMP page. The only benefit to google is if their users like the experience and continue to use Google search so they can access AMP-cached pages. If users don't like AMP, google gets no benefit.
or am i missing something?
Every AMPed page is contributing work towards improving the effectiveness and appeal of Google's product (selling ads), by adding data to the targeting algorithms.
If every piece of content on the internet is tracked -- through full UX hijack on Google's infrastructure -- that might be a trillion dollar holy grail.
People absolutely share amp links.
Also, amp being google.com hosted means no more pesky same-origin privacy protections like limiting cookies.
Google is tracking you. If you don't want to be data-mined, you shouldn't be using Google. If you are using Google, it means you don't mind being tracked. It means you are placing the convenience that Google provides above your concerns about what a faceless corporation can do with your data. If you don't mind being tracked, AMP is not a problem.
I understand how you could dislike Google. I don't understand how you could dislike AMP specifically, but not necessarily google.
But I also don’t want to end up basically deranked on Google by sites that have nothing to do with the result.
Just look at this example to see how AMP distorts the actual search ranking, by moving pages to #1 that have nothing to do with the topic, but happen to be on AMP: http://i.imgur.com/84FvZmA.png
Not sure where you think AMP is coming into this? Those results seem relevant to me?
AMP carousel pages have some subtle capture features that regular AMP pages don't. They will add more, then slowly move them to the regular AMP pages over time.