I have no idea what kind of libertarian Shermer is, but I know for sure that there are some kinds of libertarians who would take issue with the sort of libertarianism from Eliezer's self-description. Promoting the "wrong" kind of libertarianism in front of people who belong to either kind is not at all unlikely to lead to bitter and mind-killing ideological disputes.
The important difference however is that Eliezer's article presents his views in a reasonably non-confrontational way, whereas the article you linked is straight-out ideological warfare. The latter is much more likely to induce mind-killing.
I sense that I again did a poor job conveying something here, so let me try again. I am not arguing whether or not self-described libertarians of differing stripes would deny each other the libertarian label if they could -- I'm well aware how bitter the disagreements between beltway "cosmotarians" and Mises types get.
Rather, what I am saying is that I think anyone of any political leaning has a valid objection to self-described libertarians using that moniker, because the label itself is an applause light (it's not really functioning as one in...
A response essay written by Eliezer Yudkowsky posted at Cato Unbound for the issue Brain, Belief, and Politics:
Is That Your True Rejection? by Eliezer Yudkowsky
The lead essay has been written by Michael Shermer:
Liberty and Science by Michael Shermer