Yeah, the zone chat can get pretty disgusting sometimes, depending on where you are. Drozana's just pure disgusting, but DS9 (ground, space, AND even the Beta Ursae sector) draws the "intellectual disgusting" crowd, and you get political mudslinging mixed in with the more infantile insults. DS9 is either reasonable, logical discussion, or stupid Gorn jokes, or flaming. It's like a box of chocolates; you never know what you're going to get.
I can definitely attest to seeing misogynistic and racist comments, as well as other sorts of ideological bigotry.