It seems like it really is all about location and culture.
Caitlin and
Chloe may not be considered pretentious in the US, but
Imogen,
Rhiannon (I've never even heard the song, but that's probably because I'm 17 and not especially pop culture-savvy), and
Matilda are seen as old-fashioned and thus pretentious here. I've never met anyone with any of those names (although I remember seeing a
Rhiannon listed in a program for something at my school, but she had a surname that seemed to match so I didn't think anything of it), as they really aren't common here. It really is fascinating.