You're going to judge someone not by the merits of their arguments but by the topics which they've chosen to argue? That is a weak, disgusting, small-minded practice that has no place on HN. You should be ashamed.
When you're dealing with highly biased people, it can be difficult arguing their points when their argument is so obviously slanted in one direction. They only use the data that backs up their position while completely ignoring the rest of the data available.
It's like dealing with religious zealots arguing the merits of creationism. Or a better argument would be trying to convince someone that a tree is dead by pointing at the 5 brown leaves and ignoring the rest of the healthy tree.
That's why I think it's better to use the data as a whole and draw an conclusion from it. I think it is a valid argumentative style and so I think your comment was not called for.
Realistically, the only way we'll know is several years down the track. Will Microsoft be on their "long slow decline" or will this article be more FUD.
My money's on the latter, but I'm happy to be proven wrong.