Yea, but it also seems weird he wouldn't break the "no humans" rule for Hawke but he would for the Inquisitor? You can be pretty damn close to Varric in DA2.
I was pretty close to Varric as Hawke, yes. However, he's changed (I'm sure the comics and the events of the beginning of DA:I have changed him some,) and he might have wanted to keep Hawke "just friends." I was left with the impression that he told Hawke that he wasn't into humans (in a pretty easy-to-overlook conversation, where you are romancing Merrill) because he wasn't into Hawke or because Merrill was, you know, standing right there?
Anyway, I've had male best friends that I thought were attractive, but that I wasn't attracted to. It's also happened to me; guy friends would think I was cute, but they weren't into me physically/romantically.
I'd like to think a cute dwarven girl might change his mind.
And he might have never thought humans were unappealing at all, but didn't want to date Hawke specifically.