I thought I would reply before people start getting mad at one another.
I would guess that this article was written to be provocative. Not that I necessarily agree or disagree with what was said. I don't read enough to really see trends in the genre, but based on the fan base on the internet, I would say the genre is safely liberal in general.
However, many of the topics and subject matter discussed in SF are really not defined by conservative vs. liberal, but apply to people universally. Do we have to throw everything in one camp or another?
I think of Orson Scott Card's and how people loath his work because they don't like his views. I wish more people would judge the work rather than the writer. I feel some of Card's views and the way he presents them are too extreme; but most of his fiction work that I have read is solidly good writing. (No, I haven't read Empire because it does not interest me in the least.) They say he is proselyting, but most people that say that haven't read much of his stuff, or cherry pick excerpts (like from Empire). It's more based on their objection to his personal views. He really isn't a message writer. He has written religious fiction, but it is labeled as such.
But you take writers like Cory Doctorow or Paolo Bacigalupi, who are known for their message writing, nobody ever complains much about them. Why? Because they agree with what they are preaching. I happen to enjoy most of what I have read from Doctorow, but I don't think I have read anything from him where he wasn't stumping about something in one form or another. I'm not complaining. Like I said, I like his stuff, too (though he will ramble occasionally). And I am sure if I met either of them, I would like them.
Of course, all writers are influenced by their life and outlook, but from what I have noticed, Card stays more true to his characters than he does any message.
ETA: If someone makes a decision not to support Card financially because they differ with him, I understand that, but what I don't like is people criticizing his writing based on their opinion of him personally.