C!Quackity is an....interesting case. What I’ve kind of garnered from him is that during the Manburg era and New L’manburg era (in my opinion), he felt powerless. He was knocked down by a person more powerful than him (Techno, Schlatt) or a situation that was not in his control (his engagement with Karl and Sapnap). He lost a lot of things because his lost of control.
Now moving on to Las Nevadas. This is something that Quackity has control over, something that can give him power. But now, because of this overwhelming urge to keep his country in control, he doesn’t have a sense of people anymore. For example, Tubbo’s cookie outpost. Quackity’s reaction to it was, you can say, blown out of proportion. He didn’t see Tubbo as a person, he forgot about all the shit that happened to him. He saw Tubbo as a threat, as a competitor. That’s why Quackity gladly accepted Wilbur’s challenge in competing with him.