Getting in an argument (vs disagreement) in real life is worthless. Getting into an argument on the Internet has even less value.
Personally I think this was an easy article for him to write because he already had the data and he wants more subscribers (please take this take as neutral opinion and not a dis to Silver)
Yep, always good to keep in mind that the audience for public discussion is not the small number of people you're discussing with, but the large number of people reading the discussion.
That depends on what the goal is. It's worthless if you're trying to convince the other side. But in many cases, you're actually trying to convince the audience, and certainly for something like a blogpost here, I'd argue that it is not only the case, but successful, since at minimum we know it got posted to hackernews and has traction.
Personally I think this was an easy article for him to write because he already had the data and he wants more subscribers (please take this take as neutral opinion and not a dis to Silver)