My guess is it still work well for all accidental friction but won't help at all with friction Apple put in place intentionally.
Through if the appeal goes through a different person then the reviewer it might help with unreasonable reviewers (which Apple isn't probably to happy with either as they are prone to create bad PR)
I'm curious to see too, because my instinct is that accidental frictions are actually a very large chunk of the problems people have. At the scale that Apple works, even a 0.1% of updates being wrongly flagged probably meant dozens per day, and it's really annoying for a dev to have to deal with the inconsistency of randomly getting flagged for something that was fine a week ago.
My guess is it still work well for all accidental friction but won't help at all with friction Apple put in place intentionally.
Through if the appeal goes through a different person then the reviewer it might help with unreasonable reviewers (which Apple isn't probably to happy with either as they are prone to create bad PR)