I guess like most things in life there isn't a black or white answer but rather "It Depends"
While in-phone cameras continue to improve they are essentially replacements for the Point and Shoot cameras. I do wonder why manufacturers still sell them.
The Fuji X100s or t that is mentioned in the article is a different animal. It is a great camera that takes exceptional pictures. For certain genres of photography it is a clear choice. What it does require is that the photographer must move their feet to get the best shots. There is no zooming. But what do you do if there is a once in a lifetime shot of an animal that is a ways away. A 300mm or longer lens is required for the shot and you will miss it. I have wanted this or a smaller mirrorless for some time but I have not pulled the trigger yet.
The new mirrorless cameras with interchangeable lenses are appealing. The lenses are no bargain but they are for the most part superb. I think the decision here becomes personal as cost and quality for a total kit are not too far apart. Weight is the one criteria where mirrorless have an advantage.
I personally think I will stick with my full frame Nikon. I have glass covering the range from 16-500 mm and accessories to go along with it.
I think there will always be a niche for DSLR's or the equivalent in Mirrorless. Cell phones will render the point and shoot cameras obsolete and like DSLR's the fixed lens Leica or Fuji will always have a group of followers.