Assume that, instead of "race" an involuntary personal characteristic that influences, but does not determine, one's personal experiences (just compare Clarence Thomas to Louis Farrakhan) we're talking about nerds. Bookish nerds. Nerds whose personal experiences are influenced, and probably even determined, by their preference for books over the latest dance steps. By asking the question this way, it becomes a little bit clearer what's going on here. Nerds are, as a rule, more accepting of the authenticity of varied experiences of other nerds than members of visible minority x. If, for example, I told the (true) story about the substitute teacher who threw a chalkboard eraser at me in fifth grade because I pointed out the fallacy in the math story problem he was working out on the board, people would laugh, and accept that as an authentic element of the nerd experience... even if they were nerds themselves, and never themselves had had their glasses knocked off their collective faces by a teacher's errant throw, because it rings true enough by comparison to their own experiences.
The problem with a race-based argument is that race (or Catholicism in Utah, or Judiaism in rural Alabama, or anything else that is based upon a group identity) is as much a question of a Rawlsian initial position and the absence of a veil of ignorance, if not the absence of real ignorance as it is of anything else. A Rawlsian thought experiment pretty well trashes the distinction. Consider a hypothetical society that relegates to the Ghetto (in the sense of its origin in Eastern Europe) everyone whose father and mother were both born on an even minute between 1632 and 1638, and all of their descendants. Is their experience in the ghetto and, of course, any fictional description of the experience any less "authentic" because they're all fair-skinned? Or, for that matter, was Harold Abraham's experience at Cambridge (vastly different from the best-known film concerned with it) any less "authentically" Jewish? (If you think it was, his shade will probably come knee you in the groin and spit on you.)
What we have here is a misunderstanding of the difference between "correlation" and "causation," with a nod toward a theoretical problem with fiction. Race (or any other social factor) may have a strong correlation with certain experiences; in some instances, that correlation may for a period of time become so embedded in attitudes that it looks like causation. But it isn't, and that runs into the theoretical problem with fiction: With very, very, very rare exceptions, fiction is not about the truly average; it is about exception, whether exceptional experiences or exceptional people, that has been made plausible to the reader. This necessarily includes race. If Author X was writing a novel about American politics from the 1960s through the 1980s during the 1960s, I can guarantee you that every Supreme Court justice "of color" would look a lot more like Thurgood Marshall than like Clarence Thomas... and, in the end, that would be wrong, and seem racist of itself. Despite my vehement disagreement with most of his jurisprudence, Thomas's story as an exception is just plain interesting... and that's good enough for fiction. In fact, that's necessary for fiction. It is apparently, however, not necessary for teh internets.
None of this is to say that failure to do one's research is appropriate. That is never appropriate, whether one is Ralph Ellison writing about being black or Gabriel Garcia Marquez writing about a dictator. That one's research might lead to results that do not correlate perfectly to a particular reader's expectation, though especially when viewed through the funhouse lens of fiction does not justify vilification as Evil. Here's a non-race-based example that might make things a little bit clearer: The training, attitudes, and development of military officers in fiction. Not very many Americans are in a position to complain about this... because most of what Americans who haven't Been There know about military officers comes from fiction. There are so many bad examples out there particularly in military science fiction that I don't know where to begin. Compare any of those "Hornblower in Space" stories, though, to works by actual, real, no-kidding military officers like John Hemry ("Jack Campbell") which go to great lengths to get "officership" and "leadership" right <SARCASM> even though they concern the Navy <SARCASM> and then ask yourself whether the latest "space opera" bears any signs of "authenticity." If it doesn't, does it perhaps offend an identifiable group, and thereby justify heaping shame and disgrace upon the author for generations to come?
What this semitangent really points out is that what is at issue is not race, or ethnicity, or experience, or anything else; it is the question of group identity and belonging. That is a complex aspect of self that is often challenged by fiction, good or bad; and, in the end, it can be the creme filling that makes these Dolley Madison Fail Cakes marginally palatable. Or, at least, not Bad Logic Creme Fillingtm, although all too often the Bad Logic Creme Fillingtm oozes its way into other aspects of the fiction... and the conversation.
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