The user experience they wanted to achieve (provide an Apple News and Facebook Instant Articles experience on the web) was not technically possible. They added the hacks and workarounds that is AMP + AMP Cache + News carousel prerendering to Google to create something competitive.
Now they're working with the standards bodies to remove the need for the hacks they've developed. Web Packaging (for loading and verifying a bundled website - this is the preloading part) and iFrame Promotion (for 'promoting' an iFrame to the root browsing context - this is the 'clicking the search result and having the resulting page display instantly' part) is really cool and it'll be great to have this available to everyone without the downsides that Google's current solution has (URL fucking)
1 - they got caught with their hands in the cookie jar
2 - the internet isn't quite as dumb as google hoped
3 - thank god for the EU & Margrethe Vestager. Maybe we can talk her into adding a zero.
ps -- that status, as near as I can tell, of the amp url fix is vaporware. Deployed yet? Nope. So let's wait to get all triumphant until their supposed solution is deployed. https://www.androidpolice.com/2018/01/09/google-finally-fixi...