Based on decades-old material from 2e. How do you know what's in a new book? Do you always search out in-depth reviews for every single product you may wish to buy?
Yes. I do that for literally all products I buy. Doesn't matter whether it's a book, a machine, a computer component...if I don't have
at least two different "reviews" (noting that "a friend recommended it to me" qualifies as a "review" in my book), I generally won't buy a product. Food is probably the only exception there, mostly because I buy too much of it to be that scrupulous in review-getting....but I still prefer to have reviews/instructions/etc. before I do something like going to a restaurant or trying to make a particular dish.
If slavery is so important for your Dark Sun game, why can't you simply add it?
I already said my piece on that front. It isn't strictly important
to me. However, what
is important to me is creators having the freedom to explore, as I phrased it above, "evil unforgivable"....
so long as they accept the responsibility that entails. I have been
very clear about that, in
multiple different
posts. In that last one, I even explicitly (and, as usual, with far too many words) said that I do NOT use slavery in the game I run, and one of the reasons that I don't is that I did not feel up to the task. It was a responsibility I did not feel prepared for, and so I specifically and explicitly chose not to, and I told my players that up-front. Of course, the game I run isn't actually Dark Sun, it isn't even that much
like Dark Sun. I give the example not to illustrate what is or should be done with that setting, but to show that I'm putting my money where my mouth is, and that I think people should have the confidence and self-awareness to admit that maybe they just aren't in the right position to take on that responsibility.
Edit:
And the difference between slavery being an explicit part of the setting, vs. it being something each DM might elect to add personally, is exactly what I referenced earlier when explaining why
official D&D Phyrexians would maybe be too much of a problem while
homebrew Phyrexians would be an extremely useful tool (assuming the players are on board for that particular spicy meatball.) That is, the officialness really does make a difference in more than one direction. It may, yes, mean that you have to grapple with an uncomfortable topic--that may in fact be the very point. I consider slavery to be--
potentially, with caveats, and
heavy responsibility--a useful component or tool for literary work, but one that is both very dangerous and very easy to use poorly. There are plenty of IRL tools that are extremely dangerous even when used by people who should know better--consider explosives. Thankfully, the misuse of something like slavery in a written work (whether it be a book or an RPG or whatever else) is significantly less likely to kill someone than a tub of nitroglycerin. But the possibility of harm is there. All written work, fiction or nonfiction, has the potential to cause harm to
someone, somewhere, so for literally all techniques the best one can do is put in due diligence to prevent errors before they get out into the wild, and compensate for errors that you didn't catch first.