Not so much Dunmer as their fans, sort of like Portal. Now Dunmer were (intentionally) written to make people a little uncomfortable. The Dunmer mainstream culture is very racist and fairly hypocritical, openly musing whether or not any non-Dunmer are capable of enlightenment or even have souls or rational thought and treating the obviously sentient Argonians as though they were beasts of burden. They are not written as evil, however, just with a culture that is very different from our own that is difficult to change into something less racist because any changes in culture are called evil corruptions of "beasts and lesser races" by Ashlanders and temple alike. However, instead of realizing this frankly fascinating cultural exploration, a lot of Dunmer fans took this at face value as "nope, the Dunmer are right, humans, Argoniand and other elves are plainly inferior." Which leads to another interesting question: what is it about making people red-eyed, grey-skinned and pointy-eared that makes characters so much easier to bond with and being sympathetic to than any normal-looking human could ever hope to be?
Seriously, watching Dunmer fans is like looking at someone reading "Song of Ice and Fire" and agreeing with Randyll Tarly that Brienne is some kind of abomination of nature for being a woman who isn't in a kicthen or a bedroom. It's fairly disturbing.
Well said. As it regards your question, I think it has less to do with identifying with or against humans as it does a new generation's insistence on wanting to stand out and be different. Look at the huge success behind Harry Potter and Twilight--films and stories built around the notion of being different, but in a good way. These kids root for the underdog because they want to be the underdog--it's more exciting. I think people are unhappy with being the same old person doing the same old thing their parents did, and becoming the outcast or the hated is a way to jump right out of that situation and be something different.
So I don't think it makes red-eyed, grey-skinned, and pointy-eared characters more sympathetic, it just makes them the easiest way to not be "you."