The user experience is still the worst thing about AMP
My phone screen is about 10.5cm tall.
If I load an AMP page directly from its content publisher then initially I lost approximately the top 1cm to my browser's address bar, and the bottom 2/3rds of a centimetre to the navigation controls. As soon as I start scrolling downward, the bottom controls vanish and the top bar shrinks to about half a centimetre. So I've about 10cm of vertical space.
But, you know, I'm sure it gave someone something great to write in their performance review as a deployed product. So that's what Google internally considers a win.
* quite apart from the speed and deceleration not quite working correctly, the biggest tell is trying to scroll past the top of the article. The fake scroll bar alternates semi-randomly between vanishing entirely behind Google's fake address bar and being trapped inside the page content. Also if you grab the content before it snaps fully back into place after resisting your overscroll and try to scroll down, you'll find that you can't. The real OS has no such flaws: the scroll bar stays in its proper place, and you're not penalised into having to wait after daring to try to scroll too far.
So: AMP costs me almost 12% of my vertical space.