One reason why people hate the crew returning is due to being after the events of BO4 making their existence is very questionable. I don't think people would be so annoyed if Treyarch really marketed it as a complete reboot, separate from this story. Why? Because it would mean Treyarch would have to reintroduce these characters ensuring some form of writing and character development. Take Richtofens lines in Origins for example. They gave Primis a formal introduction meaning even new players would learn who they were. But with the decrease in cutscenes and voice lines in newer CODs I don't think players have much faith in Treyarch giving this new crew justice. Their cutscene is giving more "you know who these guys are" rather than "let me show you who these guys are", leveraging the old story for storytelling rather than standing on its own. And this isn't even acknowledging the fact Treyarch is presenting this new crew to be developed over the next game, whereas Origins was a single map in the present game which established the characters pretty well.