The Closet/dressing Room

It's not like I have done a frame-by-frame analysis of this, but it seems most every other scene has enormous depth. Most are against open windows, for example, with lights or the movement of the city behind the "isolated" character. Huge depth. Except the closet.

Sure, it's related to the prison cell. At around 1:09 they even jump cut from Tony on the floor of the emptied closet to his father on the floor of the prison cell. But why? Random Prison Metaphor? No. I do not get how the closet is his one prison. If anything, it's the more intangible isolation that restrains him, and the closet should be more like a reminder of the time he was with his wife and made a shared life, and got out of the isolation.

Etc. I know he "doesn't want to remember" (though shortly after this he tries to call the other girl) but more that that I want to get why the visual metaphor here is different. Earlier, his isolation was depicted differently. Tell me what you think I missed.