The author also seem to forget that there are advocates of the MIT license who would never use GPL software because of its viral nature. Does that mean Richard Stallman is 'harmful to software'? Criticize the license, but don't name-call the author who has made major positive contributions to the field.
There is a large difference here:
* The GPL is pushing an agenda in their licence, and attempts to clearly state your legal obligations.
* Crockford, on the other hand, is trying to crack a joke in a legal document. As the author states, this is dangerous to people who don't understand the legal ramifications of using this. From what I can see, the author is venting their frustration that Crockford appears to be treating the whole affair like a big joke, and I can totally understand that.