I'm not arguing mechanics, don't honestly care. As it stands, evil has a more limited access to support characters, which fits the align/class themes and balance of CF. This may be a big or not-so-big part of it.

You say you "just don't see any reason why it can't be done", but do you have a reason that it should/must be done, besides the fact that they have voices, the ability to write, and that there are paintings in K'Teng's?

You could certainly use your imagination, and attempt to RP a dark-elf "bard", just like many other characters have used the rp angle of "stuck in one class, yearning to be another". Bard doesn't fit dark-elf rp as I've always seen it: instead of singing/"art-ing" about tragic, depressing, chilling, dark, cruel ####, you instead go out and make it happen. Dark-elves are kind of go-getters like that. I see art as a secondary pursuit/consideration, if it's considered at all, for their kind. Seems more racial, therefore inherent, than cultural/learned. But now this is semantics. Like it always was. Or something.

Why do you have such a huge boner for dark-elf bards? Generally, unpickable race/class combos are bad fits for lore, mechanics, or balance reasons. Sure, there's been an elf necromancer, and other examples. But... who cares?