If you don't read slashdot enough to be able to recall the posts he speaks of, then you are not informed/qualified enough on this topic to have this discussion listing all these (arguably obviouls) truisms.
Um, or maybe the posts don't exist? This is why citations are important whenever you're going to make an argument and expect to be taken seriously.

Sure, it's MY fault that I can't prove his argument...

When someone posts something that is factual, and you don't agree with it, that is not the definition of "invalid" or "generalization".
When someone makes sweeping claims of any sort, that is the book definition of generalization. Generalization is almost completely useless as an argumentation technique because it requires the vast majority of evidence to be clearly in favor of the argument, in order for holes not to be found. But if the vast majority of evidence is already in favor of the argument, there is rarely anything to argue about!

In effect, the original post was a baseless generalization, and none of the replies did anything to defend it whatsoever. If someone wishes to make an argument, they must provide evidence beyond appealing for the reader to accept it at face value. Otherwise, it is NOISE.