I guess my point is, I think the "value" to him could likely be "because they're mine". You are implying that he kept them because he believes that they can be used at a later date as either leverage against someone or to be sold for money / favors.Making a completely different argument than MCM. I don’t disagree with your possibility. I wouldn’t be surprised in the least if Trump hasn’t looked twice at any of those boxes and doesn’t know what’s in them specifically. But that doesn’t mean he doesn’t see value in them or that he’s too shallow to understand their value.
I think it's distinctly possibly he took them because they were there.