They aren't Klingons. Not in any recognizable sense. Klingons don't torture defenseless captives. Klingons don't take sex slaves. Klingons don't eat their defeated opponents.
Yeah, completely unrecognizable. Whatever happened to the TOS "Cold War Soviets mixed with a bit of Japanese from World War II"? Where did they come up wi...wait...
https://en.wikipedia.org/wiki/Japanese_war_crimes
Japanese imperial forces employed widespread use of torture on prisoners, usually in an effort to gather military intelligence quickly.[98] Tortured prisoners were often later executed.
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Comfort women were women and girls forced into sexual slavery by the Imperial Japanese Army in occupied territories before and during World War II.[1][2][3]
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Perhaps the most senior officer convicted of cannibalism was Lt Gen. Yoshio Tachibana (立花芳夫,Tachibana Yoshio), who with 11 other Japanese personnel was tried in August 1946 in relation to the execution of U.S. Navy airmen, and the cannibalism of at least one of them, during August 1944, on Chichi Jima, in the Bonin Islands.
I wonder, is this a coincidence? In any case, all of these traits are already established Klingon behavior. Also, none of this is new either:
...the Klingons participate in self-harm, believe in rebirth in flames, and have a physical appearance that has extended their exo-skeleton
And the Klingons have always been the "other" that was feared, even when they were our friends. That Klingon lawyer built a whole case exploiting that fact:
CH'POK: Tell me, Commander, what was the final order Sompek gave to his men once they had conquered the city of Tong Vey?
DAX: He told them to burn the city to the ground and to kill everyone in it.
CH'POK: Everyone? Not just the soldiers, but the people of the town too? Civilians? Women? Children?
DAX: Yes.
CH'POK: Now, Commander, when Mister Worf runs this programme, does he give the final order to destroy the city and kill all of the inhabitants?
DAX: Yes.
CH'POK: Of course he does. Because he is a Klingon warrior. He doesn't have the same moral code as a Starfleet officer. He is one of us. A killer, a predator among sheep.
That article starts and ends with the fact that the Klingons seem evil, and misses the point. They are supposed to. Not to "dismiss the ideals" of Star Trek, but to demonstrate them. They are supposed to look like and be judged as monsters, just like the tardigrade. They are supposed to be the scary "other". The showrunners have
literally said so months ago:
I feel like one of the themes we are exploring is universal and is a lesson I feel like as human beings we have to learn over and over again – is you think you know ‘the other,’ but you really don’t.
- Gretchen Berg
And I think when people look at the Klingons – I frankly love what they represent. Not in terms necessarily of all the messaging, but in terms of learning about them and learning why they are who they are and making sure they aren’t just the enemy.
- Aaron Harberts
This is basically the whole point of season 1.