Perhaps it’s like war films, in the sense that it’s very difficult to not glamorize the subject, no matter how gritty the treatment. The worse it gets the better it looks.
This is the process of eroticization, of making distasteful things appealing, seen a lot in film. Schindler's List does this with the Holocaust, Titanic sidesteps it by overlaying a love story, Irreversible confounds it by [spoiler] ending at the beginning of the story, and so on.
Yes, on one hand the filmmaker wants to do art, and naturally searches beauty in composition, story, photography... even with the gruesomest topics.
And on the other hand even if you tell the story of someone/something reprobable, it is their story, and stories are “virus” for our empathic minds - so we end up understanding and siding with the wrong ideas / actions when they are explored (because to explore them by focusing om them turns them into the protagonist of the story).
I think to a large degree eroticization is compensatory. Check out Lodge Kerrigan or Harmony Korine for (English-language) relatively-accessible movies without the kind of clarity of dramatic structure you describe.
In other words, it isn't essential at all. Spielberg could have made a movie that represented only the helplessness, misery, and horror and left it at that.