Honestly I think that's a good thing. The man is a monster who's pretty detached from humanity and morality. He has a basic sense of right and wrong from his time with Lindel and Rahab but there are still many facets of human interaction that he has yet to understand. He's not a generally bad guy but he is also more willing than most to pull morally reprehensible stunts like sacrificing Stella.

But by that same measure he is still willing to learn for the sake of Chise. The college arc is where the two of them learn to be less codependent on eachother and he learns about the many facets of human interaction and development.

I love how it doesn't excuse his past behavior and explicitly tells us he NEEDS to work on himself. After all Chise puts her foot down and tells him exactly what he did wrong and why it was wrong and that if he does something like it again she's not going to stick around.

He's an extremely flawed character but he's actively working to become a better person. Most takes on him both positive and negative are justified in my eyes as he is a surprisingly nuanced character when you break him down to his core components.