I disagree, of course Yorda and Ico's interaction certainly are very clear, but between Yorda and her I would disagree it is obvious what the discussion is.
It is one of those things where knowing isn't important, but it's tempting to know, and they did bother to write the material to begin with. I wonder if Lost in Translation would be better, worse, or unaffected as a film by letting us know what he said to her at the end. Or if the Radiohead video for Just included what made the guy lay down.
The truth is that it's very sweet, no one should probably experience it that way first time, but they can't really anyway because it's only a new game + option.