Disagree entirely. I can see why Medium might want to move in the direction of more and shorter posts, but that doesn't change the fact that the units are posts. "The stream" is an aggregation of posts.
I honestly don't get Medium. I like some of the stuff people post on Medium, but to me it's simply another publishing platform, like Wordpress or Moveable Type or Blogger. I don't visit Medium or subscribe to it, I simply go there when following links, just like I might visit YouTube or Tumblr or Flickr. It isn't a destination, it's a vessel for destinations.
Do you agree?