Imaro
Legend
There is slavery in Star Wars. Star Wars is not a grindhouse genre of film. Star Wars is considered family friendly.
Yuan-Ti have historically been identified as slavers. Yuan-Tu slavery can be explored in a game as lightly as Anakin's slavery was in SW....or it can be explored as harshly as 12 Days a Slave.
Expecting WotC to have as hard core approach to slavery as 12 Days a Slave is too much. Expecting WotC to never mention slavery ever again is also too much. Somewhere in-between those two extremes is where I believe the proper approach lies.
Slavery is a major (some could argue THE Major) component of Dark Sun society...not a one time throwaway plot device. No one is arguing slavery can't be mentioned or exist in D&D but a one liner or reference a group can choose to use vs. your entire world being based around it aren't the same thing...