Frank, did you ever track the bug down that was causing this issue? I've tried that same article with a few different Micropub clients and I'm not seeing any issues with respect to Post Kinds finding and displaying the correct/expected data. In fact, the Atlantic actually shows quite a bit more data than most sites do.
Perhaps it's your shortcut not actually sending a URL for it to parse? I've also seen issues when trying to post content that contains special characters or emojis which WordPress tends to choke on and not understand. When a post has an emoji in the title or the body somewhere, it creates the post, but doesn't save any of the data in Post Kinds' context-related fields.