That's why game ratings were invented in the first place so those not wishing to see certain type of content are well informed in advance, if it's truly a concern.
Yes, exactly this. Unlike other media (such as television), various game ratings have and requires content warnings (namely in the Usa, U.K., Europe), it is written in their rating (most time not ingame), so people can decide then by themselves, if they purchase it or not.
That being said, most game developers try by themselves to avoid scenes that could trigger PTSD flashbacks or be declared as a glorification of violence or even being traumatizing* - by treating sensitive topics carefully, preparing the player what will happen (e.g. through the given answers), putting some scenes on off-screne or changing camera angle, incorporating them into the context or also let the player refrain from the scene. Crimsonrider did a wonderful job of describing how well very dark themes were incorporated into the story. It already starts at the beginning:
When we find the corpse "Myrnath", we can* remove an exposed brain, and if we free it, we will get this brain as limited time companion. Taking out the brain is not a glorification of violence, but serves the story.
*If we want to
*video games could also end up on an index in certain countries, if they would contain e.g. glorification of violence or violation of human dignity, that is judged to be potentially criminally.
- I love what happened to Hope because it truly puts into perspective what kind of place it is by setting the tone for the entire house and Raphael as THE devil. It's a place of eternal damnation spent in utter misery and it sends chills to even think about being imprisoned in such a place, cursed by any of the infinite fates others are suffering through in that house. Hope's form of torture wasn't even singular, as her being forced into sexual pleasure to both receive and provide was just one of countless forms of torture that Raphael continues to conduct on her in order to break her. Without her psychological traumas earned precisely by being used the way she was used, the whole significance and dread of the place comes down drastically.
It's the hardship and vile deeds that makes the setting that much more serious (and interesting) by seeing just how far an actual Devil's imagination can go and I love seeing world-building like that. Personally I found her flesh being melted while alive more disturbing than her being used for pleasure, because unlike pleasure the other one significantly scarred her to the point she never stopped hallucinating (as a defense mechanism against such unbearable pain).
- Same for Harleep, an incubus that takes over our body with no effort. It wonderfully portrays just how dark the deeds in that room are and how helpless anyone is once they enter it. I never see any praise about the absolute wonderful dread her encounter portrays by just how many souls Harleep condemned to eternally mindless sexual servitude, to be used as nothing but a warm body for sex sucked out of free will for all types of life in the hells to do with as they please.
It's so amazingly dark I wish they did more disturbing stuff like that.
Depending on the type of character I roleplay; if I am playing good I always go down for some sucky sucky with Harleep just to show her the power of sheer will. However if I'm playing evil she's an excellent conduit to eternally damn a companion to eternal sex slavery.
Like Astarion who was annoyingly pushy about having sex with my Dark Urge, so I played the long con by flirting with him as much as possible... only to then give him what he wants, just not in the way he expected; an eternity as a mindless sex slave in the hells (the others did not fare any better that run either) 
- Ethel as well. One of my favorite portrayals of hags out there because it hits so close to home about folklore tales of "Baba Yaga", an old witch that kidnaps children and performs all sort of sick curses upon them. Mothers tell these folklore stories to children to protect them from strangers and to ensure they run home when it's dark, I personally was scarred throughout my entire childhood of the dark because of the stories about Baba Yaga. I had nightmares for over a decade about her.
But see it is precisely that dread and horrific fear that truly drives forward how serious things are. Ethel perverted a thief's body into a tree to guard her home for centuries. She has a woman trapped inside a mirror eternally. Another woman holds her decapitated head in her arms still alive. Mayrina's baby was gonna get eaten by her so she can turn its corpse into her own daughter, she was probably gonna feed Mayrina to the baby later too (kinda why she says Mayrina is "marinating").
- The goblins eating a roasted Dwarf at camp and having chopped up remains deeper in the camp. That was amazingly gritty, seeing humanoids degraded into just afternoon meals for goblins who treat it as humans treat chicken. They talk so much about eating people and so on, but then Larian forbade having tiefling children killed and barely displayed it for the grove raid. I wish they kept their courage about this. If we raid the Grove have the children roasting over the fire, have a few of the druids impaled on the gates as a sign of victorious conquest. It's already implied that they're all being eaten, so have the courage to show it.
- Minthara's sex scene, because it was so graphic, wonderfully portrayed a Drow fully in heat wanting pure carnal pleasure born out of genocide committed to please her goddess. Our character used to lift their leg over Minthara's shoulder so she can go downtown, then she used that leg to push us onto our backs to perform her famous 69. It was hot, it was pure carnal pleasure, it played into the evil theme, her character (and ours)... but with full release it got so terribly tamed it entirely lost its nuance by it being just some kissing, touching and the 69. So bland in comparison.
I agree with them, well said, Crimsonrider! I was curious about Harleep and without analyzing it (only seeing it in a video - not ingame), I agree with the others, as far as I've seen, you are making a deal, the game asks for several answers to get there and you also can refrain from it, once it has started, during the act. It is dark, but well written into the story. But also importantly, the scene itself shows overall consent (though you can read it partially as dub as well), as Tav is enjoying the act with Harleep, and also after the act he is smiling (He doesn't make a face, that the act was unpleasant or he regrets sleeping with Harleep). You can refrain from the scene with a choosen answer/attacking him. If you go to the bad ending, his unpleasantness occurs from the fact, that Harleep is taking your soul and you are dying, not from the sexual act itself. The bad ending or parts of this scene may be on the verge of being or not being triggering for SA traumatized people, especially if unexpected. If this or the whole scene needs a content warning or needs to be censored but must be viewed by experts. The average player cannot decide that.
As Gray Ghost stated, I also have the feeling that some people here don't really know what PTSD flashbacks triggers and why game ratings with content warnings are done, and in general how to avoid them. I agree with Gray Ghost, people, who are not well versed in this, shouldn't judge about this so easily. For game ratings, if the game contains for example
intense violence (Scenes involving intense aggressive conflict) or sexual violence (Depictions of rape or other sexual acts)
it needs this content warning in their rating, so people could avoid to purchase and play this game. On release this game was rated and it was only rated with "violence" and "sexual content", though we don't know, which scenes they have seen.
the problem is, what people find triggering - going by recent discussions about certain face animations (please don't bring it in here, it's just an example) people seem to be triggered by very different and sometimes oppsite things.
I knew when you created this thread that you will bring this up. It is easy, if a game contains
sexual violence (Depictions of rape or other sexual acts)
it needs to get a content warning. If the scene does not depict it and it is consensual, it does not need this content warning (according to rating regulation).
That means if a person get triggered by a consensual scene, which does not contain:
sexual violence (Depictions of rape or other sexual acts)
that it is his personal trigger, which doesn't need a rating content warning (can't be avoided). Clear now? Abdirak is very much consensual, overly consensual to be honest, and not
sexual violence (Depictions of rape or other sexual acts)
Those are a few examples, but I guess all that -- the face animation, the bdsm priest, the possibility (?) to hurt minors or phobia inducing stuff like spiders - makes it hard to put everything into a trigger.
It doesn't help to lump this together, Fylimar. I kindly ask you to refrain from this.
