Yes. I think it's too early to write off Itsuki as an abusive partner. This is kinda an extreme situation, it's very understandable to react in anger. We don't know if it's a pattern.
There are clear hints it's a real pattern.
He kept the video for the right moment to nail the coffin, not letting the slighest hint he had that information
He always seems calm and composed, like he was controlling everything.
He pretend being the most humilated, but never really acted like that.
Asking both of them to get nude after all of that is really a wish to humiliated them the most.
Even when hurting his wife, he's not doing it in anger, but with control.
All of that clearly hint of a man obsessed by control, and ready to hurt someone to assess it if necessary.
Rio's cheating can't be excused, all her behaviour was trash, whatever she lived. And she didn't just cheated, she wanted to humiliate her supposed friend. But his husband is clearly trash as well. And at that moment, Rio needs some help, you can't accept that, whatever she's done (even if somehow she quite deserve it).