Salty has a .287 / .377 / .519 slash line right now; makes up for a lot of framing difficulties.
I am actually shocked that AJ is middle of the pack on this. He drops more balls than I can ever remember any catcher dropping, and that can't be good for framing. Plus, I specifically recall noting 2 consecutive terrible frames last weekend while watching with my dad, where he literally caught a curve ball into the ground on the first pitch and then on the next pitch carried a cutter further out of the strike zone.
I wonder to what extent the "framing" stat is a combination of the pitchers' command and the catchers' skill. I don't think it would be shocking to find out that it is far easier to "frame" for a pitcher that is consistently hitting his spots than it is for somebody who is all over the place. Has anyone ever looked at "framing" by comparing the starter and the backup with the same pitcher? Or maybe if the backup's sample size would be too small, look at pitchers who changed teams and see whether the two different regular catchers had similar framing stats in the adjoining years? That would be interesting.