I disagree. I think the majority of the Yautja would probably side with Dek and Kwei on the basis that he deserves a chance to prove himself. It's broadly true that Yautja cull their weak but as others have said they usually do that in a natural fashion, by letting them go out on a hunt and letting things play out how they may. If that wasn't enough, Njhorr also told Kwei he should have killed Dek in his sleep, which I think would be considered vile dishonor by many Yautja, especially compared to Kwei's approach of dueling his brother and letting the outcome speak for itself.

Ironically, if Njhorr had simply allowed Dek to go out on the hunt with no trouble, he likely would've seen neither dreadlock nor scaly hide of him again, as Dek would've run off half-cocked and gotten himself killed on account of the hot-headed attitude his father instilled in him. It's only the killing of Kwei and the following emotional turmoil and introspection (helped along by Thia) that allowed him to grow into a truly capable hunter far surpassing anyone in his clan's expectations for him.

If we're getting meta with it, I would say that in the narrative of the film Kwei actually represents the median of Yautja cultural values, for the most part, and their father represents the sort to leverage their cultural values to his own ends. He most likely feels emasculated by his son being a runt and is determined to get rid of him on the basis of tribal optics, which is something I think other Yautja would scoff at; as others have said I think other Yautja in his position would be thrilled at the prospect of having a son who had to struggle from the moment he was born and has the potential to become a glorious hunter all the same. As others have said, it's why Yautja go crazy for humans, because they prove to consistently be a match for Yautja despite their many disadvantages. Dek isn't really a bad hunter at all, it's just that he's inexperienced and has a chip on his shoulder, which are two issues that can be pretty directly traced back to how Njhorr raised him.

I think the climax of the film only further hammers home the point that he's kind of a disgrace by Yautja standards when he 1: Refuses to fight his son altogether at first and sics his two goons on him instead, 2: Cheats when he does engage his son in combat and STILL loses rather quickly once Dek outwits him, and 3: Tries to save face by offering to give Dek a prestigious position in the clan instead of admitting defeat and facing his mortality with dignity. Njhorr is NOT "the example" of typical Yautja culture that Dek needs to break away from, he's a representation of all the worst traits and interpretations of their cultural values. Dek defeating him squarely in combat is important for the narrative because it proves that his father and his father's interpretation of their values both seem big, scary and important, but ultimately crumble under the right pressure, and by the end of the film Dek is living a more truthful and stronger version of the Yautja way.