I've read the thread and ok, let's get down to specifics. Everyone seems to be keeping pretty high altitude, but, I want to really pin down what we mean here.
, your premise is that it is acceptable to include problematic elements so long as it's presented as something to be fought against. Fair enough. Let's run with that.
In the first scene of our campaign, several slave children are being torn to death by goblins in a public square for edification of the onlookers who are taking bets on which slave child will die first. You are all 1st level PC's and if you try to intervene, the local guards will kill you. Sure, you might be able to come back in a few levels, but, you cannot possibly help these people.
This would be acceptable in a D&D sourcebook published by WotC? Obviously not.
See, this is the problem right here. You want to include the "problematic material" but then run into the whole PG 13 version of the world that D&D and WotC presents. Which means any "problematic material" will always be whitewashed and sanitized. The horrors of slavery will never actually be on screen. The horrors of these various "problematic materials" cannot actually be added to the game.
And, let's be honest here, that example I wrote above is a very, very minor horror compared to the actual horrors of slavery. Or genocide. Or any other "problematic content".
So, no, I strongly oppose the idea that just because it's "something to fight" that using things like slavery or whatnot, is somehow something that WotC should be using as adventure ideas for the game. If you want to do that with your table, go right ahead. Nothing is stopping you. But, for WotC to try to deal with it in such a way that it's acceptable to millions of people? Not a chance.