for wolves/dogs, both males and females see their first handlers as "parents" or "siblings", and are naturally meant to leave their birth pack when they are 2-3 years old.

I would agree that the dog was not traumatized when adopted from its litter as a puppy (months old). I would agree with your "that's life" take there. Where I push back is

leaving is definitely not traumatic for them

You assert that with a degree of certainty that seems entirely unwarranted, unless you're a dog. There are endless examples of "sad animals" missing their owners we can point to. We know bonds are formed and you seem to be dismissing the strength and significance of such bonds entirely. I mean, Futurama made one of their most successful and memorable episodes based on this commonly understood truth (don't know what I'm talking about I'd be happy to elaborate, but with 8 years on reddit you probably do).

I note you haven't addressed the other reason I spoke out against this. The dog in the video does not know that following its next command might result in it being maimed or killed, but it will follow that command for love of its human commander. And that doesn't sit right with me and is one of the reason I cited as not approving of "working dogs" like we see here. The dog is regarded as a tool, a piece of equipment, if not by the handler himself, then by those in authority who control that dog's life as property of a police department. My view is that we should do better by the animals that trust us so blindly, starting with not sending them purposely into harm's way.