There is a difference between knowing what is wrong because you've heard it and internalizing it. This is one reason why younger employees are usually given limited responsibilities. I'm not trying to excuse his behavior, but are high school interns usually given a blog on a major publication and free reign to write whatever they want? Seems like a bad idea...
Yes, one could make the point that his boss (i.e. Arrington) should have prevented this from happening, and I'd have to agree.
I must admit to having no better argument (although I wouldn't have done such things!), but note that "not having internalized wrong" is not meaningfully different from the "too young" argument I first disagreed with.
Unless you want to suggest that it's a failure of education?
