I'd argue that having Quark be scum is acceptable character development/revelation, but it does sound like an inexcusable scene. (I forget this ep because I remember hating it...so I never watch it).
"Captive Pursuit" early in season 1 actually has a scene where Sisko discovers Quark has been requiring the Dabo girls to have sex with him, even writing it into their contracts that it's a requirement of the job, and Sisko bans him from doing so now that Starfleet is administering the station. It doesn't bother me at all here, it is a fine starting point for Quark. It just stops working by the time we get to "Profit And Lace" in late season 6.
And the PaL staging is worse -- the Dabo girl in season 1 is outraged by the demand. In season 6, we have a Dabo girl named Allura, whose only quality is that she's alluring, who has just enough lines to establish that her initial resistance was mere coyness, and she actually gets really turned on from being extorted for sex by her employer.
Also, pretty sure them racist crows were in Dumbo
There are way more cringeworthy examples of racism in cartoons than the crows in Dumbo.
Ah, of course, they were from Dumbo! And I'd certainly agree that there are plenty of worse examples of racist cartoons (just none popped to mind when I was writing that post), but the Dumbo crows are, at best, problematic. The main one is named Jim Crow! They perform a jive-talking minstrel show number, they're presented as poor and uneducated, watching today it all just feels distasteful. That being said, I definitely recognize that within the context of the time, they were actually going for something progressive with this, by portraying the crows as also being the friendly, helpful characters, so you can't indict them totally.
That makes it an interesting counterpoint to Profit And Lace -- they thought they were making an hour of television that advocated for women getting equal rights, and in the process they made an hour of TV that was also horrifically sexist. No intention, just obliviousness.