I think I saw a different scene from you then...
She was pretty hesitant about even going into the room at first.
I didn't see her "rifle through" anything.
She slowly walked around glancing at the objects in full view and seemed to reminisce perhaps about happier times with him. (thus the slight smile)
She caressed the Betrothal Bells, studied the 3D-Chess board and then walked over to his computer station.
At which point she accessed his last logs (not the entire dataload) and listened to only one (the last) which stated matter-of-factly that there was a message hidden within it.
I'm not saying here that any of that points to some kind of carnal thing, but SEX and some parts of the Star Trek Fandom, do rather seem to go hand in hand for whatever reason.
My take on that particular aspect of an unproven rumor, is that she may have tried to help Spock through his first Ponn Far with Logic (avoiding anything sexual) and the resulting calamity resulted in the discourse between them.
Part of my reasoning is the way she really didn't want to talk to Sarek about it.
