I actually agree with that diagram for the most part.
In-N-Out isn't that bad, but when they get cold, they are basically inedible, so yeah, low on the list.
And Runza's are great. I'd have them in the top three.
BK's are better than they were a few years ago, but still the inferior of the big three chains. Seems like they change theirs the most of anybody. Back in the 80s theirs used to be really good, but then they started tinkering with them, and they've never been as good since.
Chick Fil A should also be a bit higher. Better than BK and Wendys.
I also have a personal bias against any seasoned type.