No. That is literally not what anyone has been saying. I'm fine with slavery, bigotry, and stuff like that existing in worlds where it's clear that it's evil.
I'm not fine with the depiction of certain people in the setting being real world bigoted. Vistani and the Aperusa are real-world bigoted against the Romani people, and their depiction in Curse of Strahd still has them with all of the racist Romani stereotypes (drunkards, thieves, scum, etc).
I love Eberron and how Warforged are victims of racism in the setting. That's part of the draw to play a Warforged other than "magical robot man", to have to deal with the trope
What Measure is a Non-Human. Dark Sun is fine because slavery is shown to be a bad thing perpetrated by an awful system and tyrannical rulers. I like how Exandria depicts the Kryn Dynasty as being discriminated against/distrusted because they're "monstrous" races. That is all fine. That stuff can (and should) stay in the respective settings being translated to official D&D 5e products.
Having a race/culture that's whole purpose in the setting is to be laughed at by the players/readers (Gully Dwarves, Tinker Gnomes) or that reinforce real-world negative stereotypes (Romani, Aperusa, Caliban, the Red and Yellow Orcs from Orcs of Thar, etc)? No. That's not fine. That is where I draw the line.