Personally, the reason I don't go directly to medium for news is I think their content is all over the place. Some articles are about life lessons, some are about programming, some about startups, etc... If I'm reading the news, I tend to look for a given theme at any given time. If I'm working, I'm looking to read about programming stuff. If I'm watching TV and I have a laptop in front of me, I may want to read about current events Going to HN or gizmodo or ... usually presents me with a specific topic. Medium (IMO) does not.
Interesting. I just noticed today, while posting an article, that they now have additional categories which further splinter the news. It allows for more specific tagging of content but makes it harder for posters and readers to hone in on what they are interested in.