It'd be a better article if he weren't so busy mocking people on the other side of the argument from him by exaggerating to absurdity.
What I've run into, which I find discouraging for the field and personally, is SF advocates who insist that anything that isn't absolutely provably possible according to our current science is fantasy. So, for example, anything with FTL travel of any kind is actually fantasy. Which I have two problems with: (1) It assumes we've got the whole universe figured out. Um, have none of these people looked at the history of science for five consecutive seconds? Humanity has thought we had it all figured out before, and there's always been some surprise waiting to turn our whole understanding upside-down. I'm not so arrogant as to assume the universe is done with us on that score.
(2) is more concerning to me: It turns science fiction, the literature of ideas, into a dead end. How many of the scientific advances we enjoy today were created by people who were inspired by classic Star Trek and its ilk? Nobody holds Star Trek up as a bastion of scientific rigor, but what it did do was get people thinking what if.... And the same goes for a lot of the Golden Age SF; much of the science was shaky at best, or has since been thoroughly disproven, but those ideas got people thinking about ways to make them come true, and some pretty awesome stuff has come out of that pursuit. A lot of people imprinted on "science is cool!" from sources that many of SF's hardest-core fans would now insist aren't science fiction.
And that's just sad.
(For the record, I like both SF and fantasy, to the point that I generally forget to distinguish them as separate genres. Tell me a good story, I'm happy.)
(New Coke, however, was a diabolical plot against western civilization.)