Portrait mode in Pixel2 did the same thing and imo opinion worked better than portrait mode in the dual-camera iphone 7 plus (I know iphone 7 plus is older but that's the only dual camera iphone I had access to at the time).
No, the Pixel 2 and iPhone XR do the same thing. They use DPAF. In the post, you'll see that the XR's depth map actually smoothly follows the ground into the background. The Pixel 2 will do that too and it will work for inanimate objects as well.