On release it was rated mature17+ and I’ve got the impression, that Larian wants to keep this and was avoiding to get a higher rating, so a lot of things occur off-screen. The bear is offscreen, the drows are offscreen, nsfw scenes are more or less censored (though some scenes are more explicit than other scenes, only god knows why), the torture scene is more or less offscreen, as the prisoner is seen and not the wounds, so the torture doesn't glorify violence. So for this, there is no need for another warning, those things are already in the rating "Blood and Gore, Partial Nudity, Sexual Content, Strong Language, Violence". For the Harleep scene I cannot comment properly on this, as I haven't played it, but could be a scene, which could have touched the AO content, so probably Larian handled it with enough ingame hints, some overall consent and the possibility to refrain from it, if you don't like to see it.
