Than you haven't actually looked. It's everywhere.
This is what you get when you Google "female fantasy art"
Hopefully you realize the phrase "chain mail bikini" doesn't apply just to armor. The wizard wears floor length robes, unless the wizard is female in which case she wears see through harem pants and a top that shows her midriff (if not more). The female barbarian, if wearing a top at all, has a fur bikini top.
Also check out the fairly big list of examples of the Chain Mail Bikini on TV Tropes.
If that still doesn't convince you, go to the Artist's Alley at any convention. There absolutely will be more half naked women in the fantasy art, even art where the men are fully dressed.