I am taking risk saying this because I have only seen clips here and there. Forgive me if I am wrong. Been a busy day.
Hi Grace, I am sorry, I would disagree with you.
1. The thing is Aryan was shown to be private person and not shown to be naïve. Even if I take that he has relaxed since PF of Parindar, even then shouldn't he be relying on himself investigating, rather than relying on Jo or anyone else, so he doesn't make the same mistake? After all he is the one keep on advocating Imilie to not trust everyone. Only one instance I could relate to his anger against Madav is the confrontation in the office. How Madav made blunders.
2. Relationship dynamics is different. Sundar is family (I agree not all family members are reliable). Jo is a long lost friend who is reconnecting. The comfort level needs time. If you see the convo after the revelation, Sundar is gauging from both POV and care for both of their feelings. There isn't any convo to aggravate the situation. Like a true friend, a big brother. Also we know how their relationship was in tripathi family. When she left Adi, he saw her and give her the book but didn't tell anyone neither stopped her. It shows their bond and care. (When Imilie calls Sudar Bandar in front of anyone kind of give a bad taste in the mouth. He is Jiju and SIL of the family. I don't mind now and then within the family)
Jo"s convo is triggering Aryan's weak point. It's something related to his wife having an affair with someone else and pregnant with the child. I mean person like Aryan would want it to be a secret thinking of Imilie and the child he says he accepts. Especially how Narmada was against the adoption and all the dramas. It seems impulsive. I would expect Aryan to be more silent. I didn't like that he is not getting involved in the investigation and letting Jo take the upper hand in his matter. Where he isn't involving in Jo's matter. Given he is in shock, confused but he's shown to be more caring for Imilie. In our culture it's a big thing. It looks as he is letting Jo's assumption of tarnishing Imilie's character. Wouldn't he wants what's left to be protected. If this is real, it would be a skeleton in the closet. He wasn't even sharing well known issue"s pain with his own family members earlier.
In an ITV perspective, his character isn't butchered but the weight of his character is shaken. The thing is if not for this there isn't any drama. I am able to ignore the dent for the drama.