One of the nice things about writing fiction that has some didactic elements, or that has a mission and is intended to educate as well as entertain, is that it's very hard to rebut a short story. If you write an essay, someone can come along and write another essay that says your essay is rubbish. The number of people who can write a short story to rebut your short story is much smaller.If you believe that most fiction has didactic elements, at least in the sense of having theories of how people ought to behave and feel, then this becomes a pervasive justification of transformative fictional use, a response to the question "why don't you just write a review?"
Elsewhere in the quoted bits, Doctorow discusses his own reasons for making pop-culture references in his stories. I find it particularly interesting that he speaks of putting such references in his otherwise "original" stories (original in a copyright sense, anyway) because "It lets you be a fan [without] giving up authorship." Fan fiction usually does involve surrendering some incidents of authorship, but hardly all -- attribution and the resulting respect of the fan community are the key retained rights.
Doctorow continues that pop-culture references allow him to stay "a drooling fanboy without surrendering [my] position at the top of the geek hierarchy by working in these fanboy references in [my] stuff as [I] go." And this is literally true in the sense that the geek hierarchy has published sf authors at the top, with fan fiction authors occupying the middle-to-bottom positions, depending on how well they fit normative expectations for what people (mostly women) can legitimately write about. Yet as my description indicates, I was somewhat put off by Doctorow's wording because it struck me as so specifically fanboy -- a claim to cultural capital that relies on distinguishing his activities from the things that the real weirdos do. There's always a tension in any movement for cultural acceptance between insisting on the validity of alternative values and throwing the most extreme members of the group off the sled to prove that the remaining members are just normal folks. I understand why Doctorow, and to some extent Jenkins, take the normal-folks-with-benefits approach. But my fan community just got tossed off the sled.
(As a side note, Doctorow's advice about blogging seems very good.)