I'm not a fan of the slavery system. All my reasons have already been mentioned so I won't bore people with repeating and just leave it at that. That being said, I know people do like it or it wouldn't be a thing, so I just leave it alone.
I am a fan of controversial topics though, so I will address the underlying statement made by a handful, which basically amounts to arelith looking racist for having a slave system. I got two things on that.
1) Slavery is as old as civilization and has always come down to economics and power. Since the oldest civilizations our history accounts for were run by people of color, and they all had slaves in some form or another, applying racism to it can't help but be wrong. Hell, even the last bastion of slavery, good ole dixie USA, was not a racist construct. Elements of racism, in particular the belief that the african man was not as evolved as the euro man, allowed it to continue well past its societal expiration date, but at its core it was just europeans buying africans that were already enslaved by other africans because they lost war x, y, or z.
2) Assuming that people of color will see slavery in the game and get triggered is a form of racism in itself. It's the racism of low expectations. So, while I think people's hearts are in the right place, they are going about it wrong. If you want to make sure you aren't doing anything racist, it's pretty easy, just treat everyone the same as you would anyone else regardless of race/religion/whatever. Acting like they need you to save them through virtue signaling is not that.