"If the "designated areas" interpretation is that rigid, maybe we'll see the upper Yellowstone, Lamar, Snake, Heart, and Bechler opened up. (Effectively to packrafting only.)"
Except maybe Heart Lake, I doubt it. NPS is really on a straitened budget, not likely to get any larger any time soon. And as you know the Park is full of folks with no notion of proper behavior even in the tourist areas. ("Son, get a little closer to the bison so I can get you both in the picture.") Imagine them on the water. However the NPS might make an exception if a person demonstrated, in advance, packrafting knowledge and skill and a plan for a particular route. I know a couple of guys who work in Yellowstone and I'll explore it with them.
"Complaining about a backpacking mag covering packrafting is like complaining about a cooking mag covering bacon or ice cream. The awesomeness is self-evident."
If its flavor isn't improved by bacon you shouldn't be eating it.