I like that he is the Lumon rule follower. Whether it’s his fun fact about knowing the nine core principles or his suggestion that they cheer Helly up with notebook quotes. His adoration of the new handmade totes is so good when he is seen as a simple child.
Also, there are some issues. When he becomes his innie on the outside, he is shocked to learn about his innie. As he pours through his trunk, it is like he is learning all of it for the first time.
Much of the severance story is the evolution of these children into adolescence and then adults. After all, they were just born. Irving is very much a child and a rule follower. As he grows into so-called adolescence, he finds love and it’s love that eventually drives him to be more rebellious. That’s a much better story than him being reintegrated and putting on a fake show in my opinion.